get_sampled_goodness_of_fit() returns an error of get_pull() not defined

[hmwakeling]

Hi :)
The get_sampled_goodness_of_fit() returns an error of get_pull() not defined:

PyrooFit/src/pyroofit/pdf.py

Line 694 in cacd0b7

def get_sampled_goodness_of_fit(self, observable, nbins=100):