parameters: (flag_names,
                               flag_values=FLAGS, key_flag_values=None)
docstring: Declares a flag as key for the calling module.
  
    Internal function.  User code should call DECLARE_key_flag or
    ADOPT_module_key_flags instead.
  
    Args:
      flag_names: A list of strings that are names of already-registered
        Flag objects.
      flag_values: A FlagValues object that the flags listed in
        flag_names have registered with (the value of the flag_values
        argument from the DEFINE_* calls that defined those flags).
        This should almost never need to be overridden.
      key_flag_values: A FlagValues object that (among possibly many
        other things) keeps track of the key flags for each module.
        Default None means "same as flag_values".  This should almost
        never need to be overridden.
  
    Raises:
      UnrecognizedFlagError: when we refer to a flag that was not
        defined yet.
docstring_summary: Declares a flag as key for the calling module.
docstring_tokens: Declares a flag as key for the calling module .
function: def _InternalDeclareKeyFlags(flag_names,
                               flag_values=FLAGS, key_flag_values=None):
    """Declares a flag as key for the calling module.
  
    Internal function.  User code should call DECLARE_key_flag or
    ADOPT_module_key_flags instead.
  
    Args:
      flag_names: A list of strings that are names of already-registered
        Flag objects.
      flag_values: A FlagValues object that the flags listed in
        flag_names have registered with (the value of the flag_values
        argument from the DEFINE_* calls that defined those flags).
        This should almost never need to be overridden.
      key_flag_values: A FlagValues object that (among possibly many
        other things) keeps track of the key flags for each module.
        Default None means "same as flag_values".  This should almost
        never need to be overridden.
  
    Raises:
      UnrecognizedFlagError: when we refer to a flag that was not
        defined yet.
    """
    key_flag_values = key_flag_values or flag_values
  
    module = _GetCallingModule()
  
    for flag_name in flag_names:
      if flag_name not in flag_values:
        raise UnrecognizedFlagError(flag_name)
      flag = flag_values.FlagDict()[flag_name]
      key_flag_values._RegisterKeyFlagForModule(module, flag)
function_tokens: def _InternalDeclareKeyFlags ( flag_names , flag_values = FLAGS , key_flag_values = None ) : key_flag_values = key_flag_values or flag_values module = _GetCallingModule ( ) for flag_name in flag_names : if flag_name not in flag_values : raise UnrecognizedFlagError ( flag_name ) flag = flag_values . FlagDict ( ) [ flag_name ] key_flag_values . _RegisterKeyFlagForModule ( module , flag )