def neighbors_of(self, qubit: LineQubit):
"""Returns the qubits that the given qubit can interact with."""
possibles = [
LineQubit(qubit.x + 1),
LineQubit(qubit.x - 1),
]
return [e for e in possibles if e in self.qubits]
def at(self, position: int) -> Optional[LineQubit]:
"""Returns the qubit at the given position, if there is one, else None.
"""
q = LineQubit(position)
return q if q in self.qubits else None