<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def sort_rows(self, rows, section):
 """Sort the rows, as appropriate for the section. :param rows: List of tuples (all same length, same values in each position) :param section: Name of section, should match const in Differ class :return: None; rows are sorted in-place """

        #print("@@ SORT ROWS:\n{}".format(rows))
        # Section-specific determination of sort key
        if section.lower() == Differ.CHANGED.lower():
            sort_key = Differ.CHANGED_DELTA
        else:
            sort_key = None
        if sort_key is not None:
            rows.sort(key=itemgetter(sort_key))