def value_mag(self, feature_bin):
    'Return the value of a single feature_bin as a proportion of total_value.'
    return self._safe_divide(self._data.get(feature_bin), self.total_value)
Return the value of a single feature_bin as a proportion of total_value.
def value_mag(self, feature_bin):
    
    return self._safe_divide(self._data.get(feature_bin), self.total_value)