input: Write a python function to compute the Fourier transform of a given signal using numpy.
  assert np.allclose(fourierTransform(np.array([1, 2, 3, 4])), np.array([10.+0.j, -2.+2.j, -2.+0.j, -2.-2.j]))
  assert np.allclose(fourierTransform(np.array([0, 1, 0, 0])), np.array([ 1.+0.j, 0.-1.j, -1.+0.j, 0.+1.j]))
  assert np.allclose(fourierTransform(np.array([1, 0, 0, 0])), np.array([1.+0.j, 1.+0.j, 1.+0.j, 1.+0.j]))
output: import numpy as np
  
  def fourierTransform(signal):
      return np.fft.fft(signal)