code: def HasDataStream(self, name, case_sensitive=True):
      
      if not isinstance(name, py2to3.STRING_TYPES):
        raise ValueError('Name is not a string.')
  
      name_lower = name.lower()
  
      for data_stream in self._GetDataStreams():
        if data_stream.name == name:
          return True
  
        if not case_sensitive and data_stream.name.lower() == name_lower:
          return True
  
      return False
docs: Determines if the file entry has specific data stream.
  
      Args:
        name (str): name of the data stream.
        case_sensitive (Optional[bool]): True if the name is case sensitive.
  
      Returns:
        bool: True if the file entry has the data stream.
  
      Raises:
        ValueError: if the name is not string.