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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 IsDefault(self):
 """Determines if the data stream is the default data stream. Returns: bool: True if the data stream is the default data stream, false if not. """

    if not self._tsk_attribute or not self._file_system:
      return True

    if self._file_system.IsHFS():
      attribute_type = getattr(self._tsk_attribute.info, 'type', None)
      return attribute_type in (
          pytsk3.TSK_FS_ATTR_TYPE_HFS_DEFAULT, pytsk3.TSK_FS_ATTR_TYPE_HFS_DATA)

    if self._file_system.IsNTFS():
      return not bool(self.name)

    return True