(flag_name, flag_values=FLAGS)
Ensure that flag is not None during program execution.

  Registers a flag validator, which will follow usual validator
  rules.
  Args:
    flag_name: string, name of the flag
    flag_values: FlagValues
  Raises:
    AttributeError: if flag_name is not registered as a valid flag name.
Ensure that flag is not None during program execution.
Ensure that flag is not None during program execution .
def MarkFlagAsRequired(flag_name, flag_values=FLAGS):
  """Ensure that flag is not None during program execution.

  Registers a flag validator, which will follow usual validator
  rules.
  Args:
    flag_name: string, name of the flag
    flag_values: FlagValues
  Raises:
    AttributeError: if flag_name is not registered as a valid flag name.
  """
  RegisterValidator(flag_name,
                    lambda value: value is not None,
                    message='Flag --%s must be specified.' % flag_name,
                    flag_values=flag_values)
def MarkFlagAsRequired ( flag_name , flag_values = FLAGS ) : RegisterValidator ( flag_name , lambda value : value is not None , message = 'Flag --%s must be specified.' % flag_name , flag_values = flag_values )