Created run_bench to get rid of repeated test code

src/qibotn/__main__.py

@@ -21,6 +21,16 @@ def parser():
 
     return parser.parse_args()
 
+def run_bench(task, label):
+
+    start  = timer()
+    result = task()
+    end    = timer()
+    circuit_eval_time = end - start
+    print(f"Simulation time: {label} = {circuit_eval_time}s")
+    
+    return result
+
 def main(args: argparse.Namespace):
 
     print("Testing for %d nqubits" % (args.nqubits))
@@ -35,20 +45,10 @@ def main(args: argparse.Namespace):
         raise NotImplementedError(f"Cannot find circuit {circuit_name}.")
 
     myconvertor = QiboCircuitToEinsum(circuit, dtype=datatype)
-
     expression, operands = myconvertor.state_vector()
 
-    start = timer()
-    result_qibo = circuit()
-    end = timer()
-    circuit_eval_time = end - start
-    print("Simulation time: Qibo                  =",circuit_eval_time, 's')
-
-    start = timer()
-    sv_cutn = contract(expression, *operands)
-    end = timer()
-    circuit_eval_time = end - start
-    print("Simulation time: cuQuantum cuTensorNet =",circuit_eval_time, 's')    
+    result_qibo = run_bench(circuit, "Qibo")
+    sv_cutn     = run_bench(lambda:contract(expression, *operands), "cuQuantum cuTensorNet")
 
     #print(f"is sv in agreement?", cp.allclose(sv_cutn.flatten(), result_qibo.state(numpy=True)))
     assert cp.allclose(sv_cutn.flatten(), result_qibo.state(numpy=True))