Pyspark typeerror - PySpark: TypeError: 'str' object is not callable in dataframe operations. 1 *PySpark* TypeError: int() argument must be a string or a number, not 'Column' 3.

 
Solution for TypeError: Column is not iterable. PySpark add_months () function takes the first argument as a column and the second argument is a literal value. if you try to use Column type for the second argument you get “TypeError: Column is not iterable”. In order to fix this use expr () function as shown below. . Zaxbypercent27s menu with pictures

Apr 22, 2021 · pyspark: TypeError: IntegerType can not accept object in type <type 'unicode'> 3 Getting int() argument must be a string or a number, not 'Column'- Apache Spark Nov 23, 2021 · Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams May 22, 2020 · 1 Answer. Sorted by: 2. You can use sql expr using F.expr. from pyspark.sql import functions as F condition = "type_txt = 'clinic'" input_df1 = input_df.withColumn ( "prm_data_category", F.when (F.expr (condition), F.lit ("clinic")) .when (F.col ("type_txt") == 'office', F.lit ("office")) .otherwise (F.lit ("other")), ) Share. Follow. OUTPUT:-Python TypeError: int object is not subscriptableThis code returns “Python,” the name at the index position 0. We cannot use square brackets to call a function or a method because functions and methods are not subscriptable objects.pyspark / python 3.6 (TypeError: 'int' object is not subscriptable) list / tuples. 2. TypeError: tuple indices must be integers, not str using pyspark and RDD. 0.Pyspark - TypeError: 'float' object is not subscriptable when calculating mean using reduceByKey. Ask Question Asked 5 years, 6 months ago. Modified 5 years, 6 months ...6 Answers Sorted by: 61 In order to infer the field type, PySpark looks at the non-none records in each field. If a field only has None records, PySpark can not infer the type and will raise that error. Manually defining a schema will resolve the issueNov 30, 2022 · 1 Answer. In the document of createDataFrame you can see the data field must be: data: Union [pyspark.rdd.RDD [Any], Iterable [Any], ForwardRef ('PandasDataFrameLike')] Ah, I get it, to make this answer clearer. (1,) is a tuple, (1) is an integer. Hence it fulfills the iterable requirement. TypeError: 'NoneType' object is not iterable Is a python exception (as opposed to a spark error), which means your code is failing inside your udf . Your issue is that you have some null values in your DataFrame.The Jars for geoSpark are not correctly registered with your Spark Session. There's a few ways around this ranging from a tad inconvenient to pretty seamless. For example, if when you call spark-submit you specify: --jars jar1.jar,jar2.jar,jar3.jar. then the problem will go away, you can also provide a similar command to pyspark if that's your ... Hopefully figured out the issue. There were multiple installations of python and they were scattered across the file system. Fix : 1. Removed all installations of python, java, apache-spark 2.TypeError: StructType can not accept object '' in type <class 'int'> pyspark schema Hot Network Questions add_post_meta when jQuery button is clickedJun 8, 2016 · 1 Answer. Sorted by: 5. Row is a subclass of tuple and tuples in Python are immutable hence don't support item assignment. If you want to replace an item stored in a tuple you have rebuild it from scratch: ## replace "" with placeholder of your choice tuple (x if x is not None else "" for x in row) If you want to simply concatenate flat schema ... SparkSession.createDataFrame, which is used under the hood, requires an RDD / list of Row / tuple / list / dict * or pandas.DataFrame, unless schema with DataType is provided. Try to convert float to tuple like this: myFloatRdd.map (lambda x: (x, )).toDF () or even better: from pyspark.sql import Row row = Row ("val") # Or some other column ...Jul 19, 2021 · TypeError: Object of type StructField is not JSON serializable. I am trying to consume a json data stream from an Azure Event Hub to be further processed for analysis via PySpark on Databricks. I am having trouble attempting to extract the json data into data frames in a notebook. I can successfully connect to the event hub and can see the data ... TypeError: Object of type StructField is not JSON serializable. I am trying to consume a json data stream from an Azure Event Hub to be further processed for analysis via PySpark on Databricks. I am having trouble attempting to extract the json data into data frames in a notebook. I can successfully connect to the event hub and can see the data ...TypeError: field Customer: Can not merge type <class 'pyspark.sql.types.StringType'> and <class 'pyspark.sql.types.DoubleType'> 0 PySpark MapType from column values to array of column nameSep 20, 2018 · If parents is indeed an array, and you can access the element at index 0, you have to modify your comparison to something like: df_categories.parents[0] == 0 or array_contains(df_categories.parents, 0) depending on the position of the element you want to check or if you just want to know whether the value is in the array Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams I'm trying to return a specific structure from a pandas_udf. It worked on one cluster but fails on another. I try to run a udf on groups, which requires the return type to be a data frame.from pyspark.sql import SparkSession spark = SparkSession.builder.getOrCreate () # ... here you get your DF # Assuming the first column of your DF is the JSON to parse my_df = spark.read.json (my_df.rdd.map (lambda x: x [0])) Note that it won't keep any other column present in your dataset. May 22, 2020 · 1 Answer. Sorted by: 2. You can use sql expr using F.expr. from pyspark.sql import functions as F condition = "type_txt = 'clinic'" input_df1 = input_df.withColumn ( "prm_data_category", F.when (F.expr (condition), F.lit ("clinic")) .when (F.col ("type_txt") == 'office', F.lit ("office")) .otherwise (F.lit ("other")), ) Share. Follow. pyspark: TypeError: IntegerType can not accept object in type <type 'unicode'> 3 Getting int() argument must be a string or a number, not 'Column'- Apache SparkBy using the dir function on the list, we can see its method and attributes.One of which is the __getitem__ method. Similarly, if you will check for tuple, strings, and dictionary, __getitem__ will be present.Jun 19, 2022 · When running PySpark 2.4.8 script in Python 3.8 environment with Anaconda, the following issue occurs: TypeError: an integer is required (got type bytes). The environment is created using the following code: This question already has answers here : How to fix 'TypeError: an integer is required (got type bytes)' error when trying to run pyspark after installing spark 2.4.4 (8 answers) Closed 2 years ago. Created a conda environment: conda create -y -n py38 python=3.8 conda activate py38. Installed Spark from Pip: I am trying to install Pyspark in Google Colab and I got the following error: TypeError: an integer is required (got type bytes) I tried using latest spark 3.3.1 and it did not resolve the problem.Sep 5, 2022 · I am performing outlier detection in my pyspark dataframe. For that I am using an custom outlier function from here def find_outliers(df): # Identifying the numerical columns in a spark datafr... Jul 10, 2019 · I built a fasttext classification model in order to do sentiment analysis for facebook comments (using pyspark 2.4.1 on windows). When I use the prediction model function to predict the class of a sentence, the result is a tuple with the form below: In Spark < 2.4 you can use an user defined function:. from pyspark.sql.functions import udf from pyspark.sql.types import ArrayType, DataType, StringType def transform(f, t=StringType()): if not isinstance(t, DataType): raise TypeError("Invalid type {}".format(type(t))) @udf(ArrayType(t)) def _(xs): if xs is not None: return [f(x) for x in xs] return _ foo_udf = transform(str.upper) df ...Reading between the lines. You are. reading data from a CSV file. and get . TypeError: StructType can not accept object in type <type 'unicode'> This happens because you pass a string not an object compatible with struct. (a) Confuses NoneType and None (b) thinks that NameError: name 'NoneType' is not defined and TypeError: cannot concatenate 'str' and 'NoneType' objects are the same as TypeError: 'NoneType' object is not iterable (c) comparison between Python and java is "a bunch of unrelated nonsense" –TypeError: element in array field Category: Can not merge type <class 'pyspark.sql.types.StringType'> and <class 'pyspark.sql.types.DoubleType'> 0 TypeError: a float is required pysparkSep 20, 2018 · If parents is indeed an array, and you can access the element at index 0, you have to modify your comparison to something like: df_categories.parents[0] == 0 or array_contains(df_categories.parents, 0) depending on the position of the element you want to check or if you just want to know whether the value is in the array TypeError: unsupported operand type (s) for +: 'int' and 'str' Now, this does not make sense to me, since I see the types are fine for aggregation in printSchema () as you can see above. So, I tried converting it to integer just incase: mydf_converted = mydf.withColumn ("converted",mydf ["bytes_out"].cast (IntegerType ()).alias ("bytes_converted"))Mar 4, 2022 · PySpark error: TypeError: Invalid argument, not a string or column. Hot Network Questions Is a garlic bulb which is coloured brown on the outside safe to eat? ... Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams1. The Possible Issues faced when running Spark on Windows is, of not giving proper Path or by using Python 3.x to run Spark. So, Do check Path Given for spark i.e /usr/local/spark Proper or Not. Do set Python Path to Python 2.x (remove Python 3.x). Share. Improve this answer. Follow. edited Aug 3, 2017 at 9:25.1 Answer Sorted by: 6 NumPy types, including numpy.float64, are not a valid external representation for Spark SQL types. Furthermore schema you use doesn't reflect the shape of the data. You should use standard Python types, and corresponding DataType directly: spark.createDataFrame (samples.tolist (), FloatType ()).toDF ("x") ShareTypeError: element in array field Category: Can not merge type <class 'pyspark.sql.types.StringType'> and <class 'pyspark.sql.types.DoubleType'> 0 TypeError: a float is required pysparkMar 4, 2022 · PySpark error: TypeError: Invalid argument, not a string or column. Hot Network Questions Is a garlic bulb which is coloured brown on the outside safe to eat? ... 6 Answers Sorted by: 61 In order to infer the field type, PySpark looks at the non-none records in each field. If a field only has None records, PySpark can not infer the type and will raise that error. Manually defining a schema will resolve the issue*PySpark* TypeError: int() argument must be a string or a number, not 'Column' Hot Network QuestionsBy using the dir function on the list, we can see its method and attributes.One of which is the __getitem__ method. Similarly, if you will check for tuple, strings, and dictionary, __getitem__ will be present.The issue here is with F.lead() call. Third parameter (default value) is not of Column type, but this is just some constant value. If you want to use Column for default value use coalesce():Mar 31, 2021 · TypeError: StructType can not accept object 'string indices must be integers' in type <class 'str'> I tried many posts on Stackoverflow, like Dealing with non-uniform JSON columns in spark dataframe Non of it worked. Apr 13, 2023 · from pyspark.sql.functions import max as spark_max linesWithSparkGDF = linesWithSparkDF.groupBy(col("id")).agg(spark_max(col("cycle"))) Solution 3: use the PySpark create_map function Instead of using the map function, we can use the create_map function. The map function is a Python built-in function, not a PySpark function. Oct 22, 2021 · Next thing I need to do is derive the year from "REPORT_TIMESTAMP". I have tried various approaches, for instance: jsonDf.withColumn ("YEAR", datetime.fromtimestamp (to_timestamp (jsonDF.reportData.timestamp).cast ("integer")) that ended with "TypeError: an integer is required (got type Column) I also tried: Jun 19, 2022 · When running PySpark 2.4.8 script in Python 3.8 environment with Anaconda, the following issue occurs: TypeError: an integer is required (got type bytes). The environment is created using the following code: Edit: RESOLVED I think the problem is with the multi-dimensional arrays generated from Elmo inference. I averaged all the vectors and then used the final average vector for all words in the sentenc...If a field only has None records, PySpark can not infer the type and will raise that error. Manually defining a schema will resolve the issue >>> from pyspark.sql.types import StructType, StructField, StringType >>> schema = StructType([StructField("foo", StringType(), True)]) >>> df = spark.createDataFrame([[None]], schema=schema) >>> df.show ... SparkSession.createDataFrame, which is used under the hood, requires an RDD / list of Row / tuple / list / dict * or pandas.DataFrame, unless schema with DataType is provided. Try to convert float to tuple like this: myFloatRdd.map (lambda x: (x, )).toDF () or even better: from pyspark.sql import Row row = Row ("val") # Or some other column ...The issue here is with F.lead() call. Third parameter (default value) is not of Column type, but this is just some constant value. If you want to use Column for default value use coalesce():Dec 9, 2022 · I am trying to install Pyspark in Google Colab and I got the following error: TypeError: an integer is required (got type bytes) I tried using latest spark 3.3.1 and it did not resolve the problem. SparkSession.createDataFrame, which is used under the hood, requires an RDD / list of Row / tuple / list / dict * or pandas.DataFrame, unless schema with DataType is provided. Try to convert float to tuple like this: myFloatRdd.map (lambda x: (x, )).toDF () or even better: from pyspark.sql import Row row = Row ("val") # Or some other column ...Mar 13, 2021 · PySpark error: TypeError: Invalid argument, not a string or column. 0. TypeError: udf() missing 1 required positional argument: 'f' 2. unable to call pyspark udf ... TypeError: 'JavaPackage' object is not callable on PySpark, AWS Glue 0 sc._jvm.org.apache.spark.streaming.kafka.KafkaUtilsPythonHelper() TypeError: 'JavaPackage' object is not callable when usingMar 4, 2022 · PySpark error: TypeError: Invalid argument, not a string or column. Hot Network Questions Is a garlic bulb which is coloured brown on the outside safe to eat? ... Jul 4, 2022 · TypeError: 'JavaPackage' object is not callable | using java 11 for spark 3.3.0, sparknlp 4.0.1 and sparknlp jar from spark-nlp-m1_2.12 Ask Question Asked 1 year, 1 month ago TypeError: StructType can not accept object '_id' in type <class 'str'> and this is how I resolved it. I am working with heavily nested json file for scheduling , json file is composed of list of dictionary of list etc.I am trying to install Pyspark in Google Colab and I got the following error: TypeError: an integer is required (got type bytes) I tried using latest spark 3.3.1 and it did not resolve the problem.will cause TypeError: create_properties_frame() takes 2 positional arguments but 3 were given, because the kw_gsp dictionary is treated as a positional argument instead of being unpacked into separate keyword arguments. The solution is to add ** to the argument: self.create_properties_frame(frame, **kw_gsp) 1 Answer. You have to perform an aggregation on the GroupedData and collect the results before you can iterate over them e.g. count items per group: res = df.groupby (field).count ().collect () Thank you Bernhard for your comment. But actually I'm creating some index & returning it.Aug 8, 2016 · So you could manually convert the numpy.float64 to float like. df = sqlContext.createDataFrame ( [ (float (tup [0]), float (tup [1]) for tup in preds_labels], ["prediction", "label"] ) Note pyspark will then take them as pyspark.sql.types.DoubleType. This is true for string as well. So if you created your list strings using numpy , try to ... TypeError: StructType can not accept object 'string indices must be integers' in type <class 'str'> I tried many posts on Stackoverflow, like Dealing with non-uniform JSON columns in spark dataframe Non of it worked.I am working on this PySpark project, and when I am trying to calculate something, I get the following error: TypeError: int() argument must be a string or a number, not 'Column' I tried followin...Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about TeamsSep 6, 2022 · PySpark 2.4: TypeError: Column is not iterable (with F.col() usage) 9. PySpark error: AnalysisException: 'Cannot resolve column name. 0. I'm encountering Pyspark ... Mar 13, 2021 · PySpark error: TypeError: Invalid argument, not a string or column. 0. TypeError: udf() missing 1 required positional argument: 'f' 2. unable to call pyspark udf ... *PySpark* TypeError: int() argument must be a string or a number, not 'Column' Hot Network QuestionsThis is where I am running into TypeError: TimestampType can not accept object '2019-05-20 12:03:00' in type <class 'str'> or TypeError: TimestampType can not accept object 1558353780000000000 in type <class 'int'>. I have tried converting the column to different date formats in python, before defining the schema but can seem to get the import ...PySpark: Column Is Not Iterable Hot Network Questions Prepositions in Relative Clauses: Placement Rules and Exceptions (during which)You cannot use flatMap on an Int object. flatMap can be used in collection objects such as Arrays or list.. You can use map function on the rdd type that you have RDD[Integer] ...TypeError: element in array field Category: Can not merge type <class 'pyspark.sql.types.StringType'> and <class 'pyspark.sql.types.DoubleType'> 0 TypeError: a float is required pyspark1 Answer. You have to perform an aggregation on the GroupedData and collect the results before you can iterate over them e.g. count items per group: res = df.groupby (field).count ().collect () Thank you Bernhard for your comment. But actually I'm creating some index & returning it.1 Answer. Sorted by: 5. Row is a subclass of tuple and tuples in Python are immutable hence don't support item assignment. If you want to replace an item stored in a tuple you have rebuild it from scratch: ## replace "" with placeholder of your choice tuple (x if x is not None else "" for x in row) If you want to simply concatenate flat schema ...Feb 17, 2020 at 17:29 2 Does this answer your question? How to fix 'TypeError: an integer is required (got type bytes)' error when trying to run pyspark after installing spark 2.4.4 – blackbishop Feb 17, 2020 at 17:56 1 @blackbishop, No unfortunately it doesn't since downgrading is not an options for my use case. – Dmitry DeryabinPySpark error: TypeError: Invalid argument, not a string or column. 0. TypeError: udf() missing 1 required positional argument: 'f' 2. unable to call pyspark udf ...PySpark error: TypeError: Invalid argument, not a string or column. 0. TypeError: udf() missing 1 required positional argument: 'f' 2. unable to call pyspark udf ...Pyspark, TypeError: 'Column' object is not callable 1 pyspark.sql.utils.AnalysisException: THEN and ELSE expressions should all be same type or coercible to a common typefrom pyspark.sql.functions import * is bad . It goes without saying that the solution was to either restrict the import to the needed functions or to import pyspark.sql.functions and prefix the needed functions with it.Aug 13, 2018 · You could also try: import pyspark from pyspark.sql import SparkSession sc = pyspark.SparkContext ('local [*]') spark = SparkSession.builder.getOrCreate () . . . spDF.createOrReplaceTempView ("space") spark.sql ("SELECT name FROM space").show () The top two lines are optional to someone to try this snippet in local machine. Share. Aug 27, 2018 · The answer of @Tshilidzi Madau is correct - what you need to do is to add mleap-spark jar into your spark classpath. One option in pyspark is to set the spark.jars.packages config while creating the SparkSession: from pyspark.sql import SparkSession spark = SparkSession.builder \ .config ('spark.jars.packages', 'ml.combust.mleap:mleap-spark_2 ... Apr 7, 2022 · By using the dir function on the list, we can see its method and attributes.One of which is the __getitem__ method. Similarly, if you will check for tuple, strings, and dictionary, __getitem__ will be present. TypeError: StructType can not accept object '' in type <class 'int'> pyspark schema Hot Network Questions add_post_meta when jQuery button is clickedclass PySparkValueError (PySparkException, ValueError): """ Wrapper class for ValueError to support error classes. """ class PySparkTypeError (PySparkException, TypeError): """ Wrapper class for TypeError to support error classes. """ class PySparkAttributeError (PySparkException, AttributeError): """ Wrapper class for AttributeError to support ... Dec 31, 2018 · PySpark: TypeError: 'str' object is not callable in dataframe operations. 1 *PySpark* TypeError: int() argument must be a string or a number, not 'Column' 3. Jan 31, 2023 · The issue here is with F.lead() call. Third parameter (default value) is not of Column type, but this is just some constant value. If you want to use Column for default value use coalesce(): Oct 19, 2022 · The transactions_df is the DF I am running my UDF on and inside the UDF I am referencing another DF to get values from based on some conditions. def convertRate(row): completed = row[&quot; Dec 1, 2019 · TypeError: field date: DateType can not accept object '2019-12-01' in type <class 'str'> I tried to convert stringType to DateType using to_date plus some other ways but not able to do so. Please advise I'm working on a spark code, I always got error: TypeError: 'float' object is not iterable on the line of reduceByKey() function. Can someone help me? This is the stacktrace of the error: d[k] =...1 Answer Sorted by: 6 NumPy types, including numpy.float64, are not a valid external representation for Spark SQL types. Furthermore schema you use doesn't reflect the shape of the data. You should use standard Python types, and corresponding DataType directly: spark.createDataFrame (samples.tolist (), FloatType ()).toDF ("x") Share

1 Answer. You have to perform an aggregation on the GroupedData and collect the results before you can iterate over them e.g. count items per group: res = df.groupby (field).count ().collect () Thank you Bernhard for your comment. But actually I'm creating some index & returning it.. Rancher

pyspark typeerror

Sep 5, 2022 · I am performing outlier detection in my pyspark dataframe. For that I am using an custom outlier function from here def find_outliers(df): # Identifying the numerical columns in a spark datafr... The following gives me a TypeError: Column is not iterable exception: from pyspark.sql import functions as F df = spark_sesn.createDataFrame([Row(col0 = 10, c...1. Change DataType using PySpark withColumn () By using PySpark withColumn () on a DataFrame, we can cast or change the data type of a column. In order to change data type, you would also need to use cast () function along with withColumn (). The below statement changes the datatype from String to Integer for the salary column.class PySparkValueError(PySparkException, ValueError): """ Wrapper class for ValueError to support error classes. """ class PySparkTypeError(PySparkException, TypeError): """ Wrapper class for TypeError to support error classes. """ class PySparkAttributeError(PySparkException, AttributeError): """ Wrapper class for AttributeError to support err...def decorated_ (x): ... decorated = decorator (decorated_) So Pipeline.__init__ is actually a functools.wrapped wrapper which captures defined __init__ ( func argument of the keyword_only) as a part of its closure. When it is called, it uses received kwargs as a function attribute of itself.总结. 在本文中,我们介绍了PySpark中的TypeError: ‘JavaPackage’对象不可调用错误,并提供了解决方案和示例代码进行说明。. 当我们遇到这个错误时,只需要正确地调用相应的函数,并遵循正确的语法即可解决问题。. 学习正确使用PySpark的函数调用方法,将会帮助 ... TypeError: 'NoneType' object is not iterable Is a python exception (as opposed to a spark error), which means your code is failing inside your udf . Your issue is that you have some null values in your DataFrame.总结. 在本文中,我们介绍了PySpark中的TypeError: ‘JavaPackage’对象不可调用错误,并提供了解决方案和示例代码进行说明。. 当我们遇到这个错误时,只需要正确地调用相应的函数,并遵循正确的语法即可解决问题。. 学习正确使用PySpark的函数调用方法,将会帮助 ... Apr 22, 2021 · pyspark: TypeError: IntegerType can not accept object in type <type 'unicode'> 3 Getting int() argument must be a string or a number, not 'Column'- Apache Spark 10. Its because you are trying to apply the function contains to the column. The function contains does not exist in pyspark. You should try like. Try this: import pyspark.sql.functions as F df = df.withColumn ("AddCol",F.when (F.col ("Pclass").like ("3"),"three").otherwise ("notthree")) Or if you just want it to be exactly the number 3 you ...In Spark < 2.4 you can use an user defined function:. from pyspark.sql.functions import udf from pyspark.sql.types import ArrayType, DataType, StringType def transform(f, t=StringType()): if not isinstance(t, DataType): raise TypeError("Invalid type {}".format(type(t))) @udf(ArrayType(t)) def _(xs): if xs is not None: return [f(x) for x in xs] return _ foo_udf = transform(str.upper) df ... Nov 23, 2021 · Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams import pyspark # only run after findspark.init() from pyspark.sql import SparkSession spark = SparkSession.builder.getOrCreate() df = spark.sql('''select 'spark' as hello ''') df.show() but when i try the following afterwards it crashes with the error: "TypeError: 'JavaPackage' object is not callable"The psdf.show() does not work although DataFrame looks to be created. I wonder what is the cause of this. The environment is Pyspark:3.2.1-hadoop3.2 Hadoop:3.2.1 JDK: 18.0.1.1 local The code is theMay 16, 2020 · unexpected type: <class 'pyspark.sql.types.DataTypeSingleton'> when casting to Int on a ApacheSpark Dataframe 4 PySpark: TypeError: StructType can not accept object 0.10000000000000001 in type <type 'numpy.float64'> In Spark < 2.4 you can use an user defined function:. from pyspark.sql.functions import udf from pyspark.sql.types import ArrayType, DataType, StringType def transform(f, t=StringType()): if not isinstance(t, DataType): raise TypeError("Invalid type {}".format(type(t))) @udf(ArrayType(t)) def _(xs): if xs is not None: return [f(x) for x in xs] return _ foo_udf = transform(str.upper) df ... I am working on this PySpark project, and when I am trying to calculate something, I get the following error: TypeError: int() argument must be a string or a number, not 'Column' I tried followin...*PySpark* TypeError: int() argument must be a string or a number, not 'Column' Hot Network Questions Can a group generated by its involutions, the product of every two of which has order a power of 2, have an element of odd order?.

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