(self, key, value)
Setting tag[key] sets the value of the 'key' attribute for the
        tag.
Setting tag[key] sets the value of the 'key' attribute for the
        tag.
Setting tag [ key ] sets the value of the key attribute for the tag .
def __setitem__(self, key, value):
        """Setting tag[key] sets the value of the 'key' attribute for the
        tag."""
        self.attrs[key] = value
def __setitem__ ( self , key , value ) : self . attrs [ key ] = value