Fix ploop.1.py example

Author: ggeorgakoudis

examples/ploop.1.py

@@ -1,13 +1,14 @@
-import numba
+from numba.openmp import njit
 from numba.openmp import openmp_context as openmp
-from numba.openmp import omp_set_num_threads, omp_get_thread_num, omp_get_num_threads, omp_get_wtime
 import numpy as np
 
-@numba.njit
+
+@njit
 def simple(n, a, b):
     with openmp("parallel for"):
         for i in range(1, n):
-            b[i] = (a[i] + a[i-1]) / 2.0
+            b[i] = (a[i] + a[i - 1]) / 2.0
+
 
 a = np.ones(100)
 b = np.empty(len(a))