code: def chebyshev(coefs, time, domain):
      
      return Chebyshev(coefs, domain=domain)(time) - 0.5 * coefs[0]
docs: Evaluate a Chebyshev Polynomial
  
      Args:
          coefs (list, np.array): Coefficients defining the polynomial
          time (int, float): Time where to evaluate the polynomial
          domain (list, tuple): Domain (or time interval) for which the polynomial is defined: [left, right]
  
      Reference: Appendix A in the MSG Level 1.5 Image Data Format Description.