input: Write a python function to calculate the sinusoidal wave given an input array.
  assert np.allclose(sinusoidal_wave(np.array([0, 0.25, 0.5, 0.75, 1])), np.sin(2*np.pi*np.array([0, 0.25, 0.5, 0.75, 1])))
  assert np.allclose(sinusoidal_wave(np.array([0, 1, 2])), np.sin(2*np.pi*np.array([0, 1, 2])))
  assert np.allclose(sinusoidal_wave(np.array([0.1, 0.2, 0.3])), np.sin(2*np.pi*np.array([0.1, 0.2, 0.3])))
output: import numpy as np
  
  def sinusoidal_wave(input_array):
      return np.sin(2 * np.pi * input_array)