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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 ParseEnum(field, value):
 """Parse an enum value. The value can be specified by a number (the enum value), or by a string literal (the enum name). Args: field: Enum field descriptor. value: String value. Returns: Enum value number. Raises: ValueError: If the enum value could not be parsed. """

  enum_descriptor = field.enum_type
  try:
    number = int(value, 0)
  except ValueError:
    # Identifier.
    enum_value = enum_descriptor.values_by_name.get(value, None)
    if enum_value is None:
      raise ValueError('Enum type "%s" has no value named %s.' %
                       (enum_descriptor.full_name, value))
  else:
    # Numeric value.
    enum_value = enum_descriptor.values_by_number.get(number, None)
    if enum_value is None:
      raise ValueError('Enum type "%s" has no value with number %d.' %
                       (enum_descriptor.full_name, number))
  return enum_value.number