new_contents: import numpy as np
  from stingray.pulse.modeling import fitSinc
  
  np.random.seed(0)
  
  def test_sinc_function():
      x = np.linspace(-5., 5., 200)
      y = 2 * (np.sin(x)/x)**2
      y += np.random.normal(0., 0.1, x.shape)
  
      s = fitSinc(x,y)
      
      assert np.abs(s.mean) < 0.1 
      assert np.abs(s.amplitude - 1) < 0.1 
      assert np.abs(s.width - 1) < 0.1
  
subject: Add tests for sinc