cell magic %%dax returning error

Hi,

I noticed a syntax error in my previously supplied code and I've tried using fabric.evaluate_dax() as you suggest:

df_dax = fabric.evaluate_dax(
    dataset = "REDACTED", \
    workspace = "REDACTED", \
    dax_string = 
    """
    EVALUATE
    SUMMARIZECOLUMNS (
        'dim_date'[calendar_start_of_week],
        'dim_ga_session'[ga_page_path_session_landing],
        'dim_ga_session'[ga_is_login_session],
        'dim_ga_session'[ga_channel],
        'dim_ga_session'[ga_site_variant],
        FILTER (
            KEEPFILTERS ( VALUES ( 'dim_date'[calendar_start_of_week] ) ),
            'dim_date'[calendar_start_of_week] >= DATE ( 2014, 1, 1 )
        ),
        TREATAS ( { "Canada" }, 'dim_ga_session'[ga_site_variant] ),
        "sessions", 'model_metrics'[# Sessions],
        "bounce_sessions", 'model_metrics'[# Bounce Sessions]
    )
    """
)

However this code still generates an error:

---------------------------------------------------------------------------
NotSupportedException                     Traceback (most recent call last)
NotSupportedException: type System.Object is not supported
   at Parquet.Schema.DataField..ctor(String name, Type clrType, Nullable`1 isNullable, Nullable`1 isArray, String propertyName)
   at Parquet.Schema.DataField`1..ctor(String name, Nullable`1 nullable)

The above exception was the direct cause of the following exception:

TargetInvocationException                 Traceback (most recent call last)
TargetInvocationException: Exception has been thrown by the target of an invocation.
 ---> System.NotSupportedException: type System.Object is not supported
   at Parquet.Schema.DataField..ctor(String name, Type clrType, Nullable`1 isNullable, Nullable`1 isArray, String propertyName)
   at Parquet.Schema.DataField`1..ctor(String name, Nullable`1 nullable)
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Span`1& arguments, Signature sig, Boolean constructor, Boolean wrapExceptions)
   at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture)
   at System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.GetFields(AdomdDataReader reader)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.WriteAsync(AdomdDataReader reader)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.WriteAsync()

The above exception was the direct cause of the following exception:

AggregateException                        Traceback (most recent call last)
Cell In[43], line 1
----> 1 df_dax = fabric.evaluate_dax(
      2     dataset = "REDACTED", \
      3     workspace = "REDACTED", \
      4     dax_string = 
      5     """
      6     EVALUATE
      7     SUMMARIZECOLUMNS (
      8         'dim_date'[calendar_start_of_week],
      9         'dim_ga_session'[ga_page_path_session_landing],
     10         'dim_ga_session'[ga_is_login_session],
     11         'dim_ga_session'[ga_channel],
     12         'dim_ga_session'[ga_site_variant],
     13         FILTER (
     14             KEEPFILTERS ( VALUES ( 'dim_date'[calendar_start_of_week] ) ),
     15             'dim_date'[calendar_start_of_week] >= DATE ( 2014, 1, 1 )
     16         ),
     17         TREATAS ( { "United Kingdom" }, 'dim_ga_session'[ga_site_variant] ),
     18         "sessions", 'model_metrics'[# Sessions],
     19         "bounce_sessions", 'model_metrics'[# Bounce Sessions]
     20     )
     21     """
     22 )

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/_utils/_log.py:269, in mds_log.<locals>.get_wrapper.<locals>.log_decorator_wrapper(*args, **kwargs)
    266     raise
    268 try:
--> 269     result = func(*args, **kwargs)
    271     # The invocation for get_message_dict moves after the function
    272     # so it can access the state after the method call
    273     message.update(extractor.get_completion_message_dict(result, arg_dict))

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/fabric/_flat.py:891, in evaluate_dax(dataset, dax_string, workspace, verbose)
    869 """
    870 Compute `DAX <https://learn.microsoft.com/en-us/dax/>`_ query for a given dataset.
    871 
   (...)
    888     :class:`~sempy.fabric.FabricDataFrame` holding the result of the DAX query.
    889 """
    890 client: DatasetXmlaClient = _get_or_create_workspace_client(workspace).get_dataset_client(dataset, mode=ConnectionMode.XMLA)  # type: ignore
--> 891 return client.evaluate_dax(dax_string, verbose)

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/fabric/_client/_base_dataset_client.py:103, in BaseDatasetClient.evaluate_dax(self, query, verbose)
     87 def evaluate_dax(self, query: str, verbose: int = 0) -> FabricDataFrame:
     88     """
     89     Retrieve results of DAX query as a FabricDataFrame.
     90 
   (...)
    101         FabricDataFrame converted from the results of a DAX query.
    102     """
--> 103     df = self._evaluate_dax(query, verbose)
    104     return FabricDataFrame(df, dataset=self._dataset_name, workspace=self._workspace_client.get_workspace_name())

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/fabric/_client/_dataset_xmla_client.py:68, in DatasetXmlaClient._evaluate_dax(self, query, verbose, batch_size)
     67 def _evaluate_dax(self, query: str, verbose: int = 0, batch_size: int = 100000) -> pd.DataFrame:
---> 68     return self._get_DAX(dax_string=query, batch_size=batch_size, verbose=verbose)

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/_utils/_log.py:269, in mds_log.<locals>.get_wrapper.<locals>.log_decorator_wrapper(*args, **kwargs)
    266     raise
    268 try:
--> 269     result = func(*args, **kwargs)
    271     # The invocation for get_message_dict moves after the function
    272     # so it can access the state after the method call
    273     message.update(extractor.get_completion_message_dict(result, arg_dict))

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/fabric/_client/_dataset_xmla_client.py:195, in DatasetXmlaClient._get_DAX(self, dax_string, batch_size, verbose)
    193         df, fields = dax_to_parquet()
    194     else:
--> 195         raise e
    197 return self._convert_dtypes(df, fields)

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/fabric/_client/_dataset_xmla_client.py:185, in DatasetXmlaClient._get_DAX(self, dax_string, batch_size, verbose)
    182             pass
    184 try:
--> 185     df, fields = dax_to_parquet()
    186 except AdomdConnectionException:
    187     # retry on connection error - examples include "The connection either timed out or was lost." or "The request was routed to the wrong node"
    188     df, fields = dax_to_parquet()

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/_utils/_log.py:269, in mds_log.<locals>.get_wrapper.<locals>.log_decorator_wrapper(*args, **kwargs)
    266     raise
    268 try:
--> 269     result = func(*args, **kwargs)
    271     # The invocation for get_message_dict moves after the function
    272     # so it can access the state after the method call
    273     message.update(extractor.get_completion_message_dict(result, arg_dict))

File ~/cluster-env/clonedenv/lib/python3.10/site-packages/sempy/fabric/_client/_dataset_xmla_client.py:168, in DatasetXmlaClient._get_DAX.<locals>.dax_to_parquet()
    166 try:
    167     with self.get_adomd_connection() as adomd_connection:
--> 168         fields = ParquetWriter.DAXToParquet(
    169             dax_string,
    170             temp_file_name,
    171             batch_size,
    172             adomd_connection,
    173             verbose
    174         )
    175         df = pd.read_parquet(temp_file_name)
    176         return df, fields

AggregateException: One or more errors occurred. (Exception has been thrown by the target of an invocation.)
 ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation.
 ---> System.NotSupportedException: type System.Object is not supported
   at Parquet.Schema.DataField..ctor(String name, Type clrType, Nullable`1 isNullable, Nullable`1 isArray, String propertyName)
   at Parquet.Schema.DataField`1..ctor(String name, Nullable`1 nullable)
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Span`1& arguments, Signature sig, Boolean constructor, Boolean wrapExceptions)
   at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture)
   at System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.GetFields(AdomdDataReader reader)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.WriteAsync(AdomdDataReader reader)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.WriteAsync()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Microsoft.Fabric.SemanticLink.ParquetWriter.DAXToParquet(String dax, String fileName, Int32 batchSize, AdomdConnection adomdConnection, Int32 verbose)