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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 __validate_path_parameters(self, field, path_parameters):
 """Verifies that all path parameters correspond to an existing subfield. Args: field: An instance of a subclass of messages.Field. Should be the root level property name in each path parameter in path_parameters. For example, if the field is called 'foo', then each path parameter should begin with 'foo.'. path_parameters: A list of Strings representing URI parameter variables. Raises: TypeError: If one of the path parameters does not start with field.name. """

    for param in path_parameters:
      segment_list = param.split('.')
      if segment_list[0] != field.name:
        raise TypeError('Subfield %r can\'t come from field %r.'
                        % (param, field.name))
      self.__validate_simple_subfield(field.name, field, segment_list[1:])