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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 _check_enum(parameter_name, value, parameter_config):
 """Checks if an enum value is valid. This is called by the transform_parameter_value function and shouldn't be called directly. This verifies that the value of an enum parameter is valid. Args: parameter_name: A string containing the name of the parameter, which is either just a variable name or the name with the index appended. For example 'var' or 'var[2]'. value: A string containing the value passed in for the parameter. parameter_config: The dictionary containing information specific to the parameter in question. This is retrieved from request.parameters in the method config. Raises: EnumRejectionError: If the given value is not among the accepted enum values in the field parameter. """

  enum_values = [enum['backendValue']
                 for enum in parameter_config['enum'].values()
                 if 'backendValue' in enum]
  if value not in enum_values:
    raise errors.EnumRejectionError(parameter_name, value, enum_values)