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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 _ParseNumericOption(cls, options, argument_name, default_value=None):
 """Parses a numeric command line argument. Args: options (argparse.Namespace):
 parser options. argument_name (str):
 name of the command line argument. default_value (Optional[int]):
 default value of the command line argument. Returns: int: command line argument value or the default value if the command line argument is not set Raises: BadConfigOption: if the command line argument value cannot be converted to a Unicode string. """

    argument_value = getattr(options, argument_name, None)
    if argument_value is None:
      return default_value

    if not isinstance(argument_value, py2to3.INTEGER_TYPES):
      raise errors.BadConfigOption(
          'Unsupported option: {0:s} integer type required.'.format(
              argument_name))

    return argument_value