lint fixes

Author: Mayank447

src/qutip_qip/device/__init__.py

@@ -25,5 +25,5 @@
     "LinearSpinChain",
     "CircularSpinChain",
     "SpinChainModel",
-    "OptPulseProcessor"
+    "OptPulseProcessor",
 ]

src/qutip_qip/device/processor.py

@@ -70,7 +70,7 @@ class Processor(object):
 
     def __init__(
         self,
-        num_qubits,
+        num_qubits=None,
         dims=None,
         spline_kind="step_func",
         model=None,

src/qutip_qip/qasm.py

@@ -7,7 +7,7 @@
 import warnings
 
 import numpy as np
-from math import pi # Don't remove
+from math import pi  # Don't remove
 
 from .circuit import QubitCircuit
 from .operations import (