[bug] Couldn't use (model.resid)

[HebahAlshamlan]

Hi, This is really a great job! thank you i learn a lot from it and from the references you mention.
Anyway, when I try to run any cell contains model.resid
I get this error

AttributeError                            Traceback (most recent call last)
<ipython-input-137-c4481da1ff48> in <module>()
     25     print('If the returned Anderson Draling statistic is larger than the critical value, then for the 5% significance level, the null hypothesis that the data come from the Normal distribution should be rejected. ')
     26 
---> 27 normality_of_residuals_test(lm)

<ipython-input-137-c4481da1ff48> in normality_of_residuals_test(model)
     10     '''
     11 
---> 12     sm.ProbPlot(model.resid).qqplot(line='s');
     13     plt.title('Q-Q plot');
     14 

AttributeError: 'LinearRegression' object has no attribute 'resid'