Method pop

Lib/collections/__init__.py:1137–1142

Remove *key* from maps[0] and return its value. Raise KeyError if *key* not in maps[0].

(self, key, *args)

            raise KeyError('No keys found in the first mapping.')

    def pop(self, key, *args):
        'Remove *key* from maps[0] and return its value. Raise KeyError if *key* not in maps[0].'
        try:
            return self.maps[0].pop(key, *args)
        except KeyError:
            raise KeyError(f'Key not found in the first mapping: {key!r}')

    def clear(self):
        'Clear maps[0], leaving maps[1:] intact.'