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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _calc_map_expectation_success(self, success_count, nonnull_count, mostly):
 """Calculate success and percent_success for column_map_expectations Args: success_count (int):
 \ The number of successful values in the column nonnull_count (int):
 \ The number of nonnull values in the column mostly (float or None):
 \ A value between 0 and 1 (or None), indicating the percentage of successes required to pass the expectation as a whole\ If mostly=None, then all values must succeed in order for the expectation as a whole to succeed. Returns: success (boolean), percent_success (float) """


        if nonnull_count > 0:
            # percent_success = float(success_count)/nonnull_count
            percent_success = success_count / nonnull_count

            if mostly != None:
                success = bool(percent_success >= mostly)

            else:
                success = bool(nonnull_count-success_count == 0)

        else:
            success = True
            percent_success = None

        return success, percent_success