parameters: (self, label)
docstring: Add label to list of labels on the message.
docstring_summary: Add label to list of labels on the message.
docstring_tokens: Add label to list of labels on the message .
function: def add_label(self, label):
          """Add label to list of labels on the message."""
          if isinstance(label, str):
              if label not in self._labels:
                  self._labels.append(label)
          else:
              raise TypeError('label must be a string: %s' % type(label))
function_tokens: def add_label ( self , label ) : if isinstance ( label , str ) : if label not in self . _labels : self . _labels . append ( label ) else : raise TypeError ( 'label must be a string: %s' % type ( label ) )