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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 _ReadPresetsFromFileObject(self, file_object):
 """Reads parser and parser plugin presets from a file-like object. Args: file_object (file):
 file-like object containing the parser and parser plugin presets definitions. Yields: ParserPreset: a parser preset. Raises: MalformedPresetError: if one or more plugin preset definitions are malformed. """

    yaml_generator = yaml.safe_load_all(file_object)

    last_preset_definition = None
    for yaml_definition in yaml_generator:
      try:
        preset_definition = self._ReadParserPresetValues(yaml_definition)
      except errors.MalformedPresetError as exception:
        error_location = 'At start'
        if last_preset_definition:
          error_location = 'After: {0:s}'.format(last_preset_definition.name)

        raise errors.MalformedPresetError(
            '{0:s} {1!s}'.format(error_location, exception))

      yield preset_definition
      last_preset_definition = preset_definition