code: def DampedPowerlaw(q, a, alpha, sigma):
      
      return a * q ** alpha * np.exp(-q ** 2 / (2 * sigma ** 2))
docs: Damped power-law
  
      Inputs:
      -------
          ``q``: independent variable
          ``a``: factor
          ``alpha``: exponent
          ``sigma``: hwhm of the damping Gaussian
  
      Formula:
      --------
          ``a*q^alpha*exp(-q^2/(2*sigma^2))``