code: def parametric_line(x, y):
      
      if len(x) != len(y):
          raise ValueError("Arrays must be the same length")
  
      X = np.ones((len(x), len(x)))*np.nan
      Y = X.copy()
  
      for i in range(len(x)):
          X[i, :(i+1)] = x[:(i+1)]
          Y[i, :(i+1)] = y[:(i+1)]
      return X, Y
docs: Parameters
      ----------
      x : 1D numpy array
      y : 1D numpy array