diff --git a/src/quantum_circuit/quantum_circuit.py b/src/quantum_circuit/quantum_circuit.py
index def53f1..b819377 100644
--- a/src/quantum_circuit/quantum_circuit.py
+++ b/src/quantum_circuit/quantum_circuit.py
@@ -36,7 +36,7 @@ def __init__(
 
         elif self.gpu:
             try:
-                check = subprocess.check_output(["nvcc", "--version"]).decode()
+                subprocess.check_output(["nvcc", "--version"]).decode()
                 self.calculator = GpuCalculator(qubits, big_endian, prep)
             except FileNotFoundError:
                 print("ERROR: CUDA NOT INSTALLED. SWITCHING TO BASE...")
diff --git a/src/tools/amplitude.py b/src/tools/amplitude.py
index aeb10b2..b502f21 100644
--- a/src/tools/amplitude.py
+++ b/src/tools/amplitude.py
@@ -5,7 +5,6 @@
 
 def amplitude(quantumstate, show_bit=-1, round: int = 3, radian: bool = False):
     quantumstate = convert_state(quantumstate)
-    size = int(log2(quantumstate.size))
     ToolsException().test_amplitude(show_bit, round, amplitude)
     if isinstance(show_bit, int) and show_bit < 0:
         amplitude = sqrt(power(quantumstate.real, 2) + power(quantumstate.imag, 2))
diff --git a/src/visualize/q_sphere.py b/src/visualize/q_sphere.py
index 54f7ce8..9cd6047 100644
--- a/src/visualize/q_sphere.py
+++ b/src/visualize/q_sphere.py
@@ -10,7 +10,6 @@
 )
 from ..tools import probability, phaseangle
 
-
 def q_sphere(
     circuit: any,
     path: str = "qsphere.png",