code: def PHASE(angle, qubit):
      
      return Gate(name="PHASE", params=[angle], qubits=[unpack_qubit(qubit)])
docs: Produces the PHASE gate::
  
          PHASE(phi) = [[1, 0],
                        [0, exp(1j * phi)]]
  
      This is the same as the RZ gate.
  
      :param angle: The angle to rotate around the z-axis on the bloch sphere.
      :param qubit: The qubit apply the gate to.
      :returns: A Gate object.