code: def gaussian(x, mu, sigma):
      
      return _np.exp(-(x-mu)**2/(2*sigma**2)) / (_np.sqrt(2*_np.pi) * sigma)
docs: Gaussian function of the form :math:`\\frac{1}{\\sqrt{2 \\pi}\\sigma} e^{-\\frac{(x-\\mu)^2}{2\\sigma^2}}`.
  
      .. versionadded:: 1.5
  
      Parameters
      ----------
      x : float
          Function variable :math:`x`.
      mu : float
          Mean of the Gaussian function.
      sigma : float
          Standard deviation of the Gaussian function.