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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _GetDataTypeMap(self, name):
 """Retrieves a data type map defined by the definition file. The data type maps are cached for reuse. Args: name (str):
 name of the data type as defined by the definition file. Returns: dtfabric.DataTypeMap: data type map which contains a data type definition, such as a structure, that can be mapped onto binary data. """

    data_type_map = self._data_type_maps.get(name, None)
    if not data_type_map:
      data_type_map = self._fabric.CreateDataTypeMap(name)
      self._data_type_maps[name] = data_type_map

    return data_type_map