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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 _select_sql(self, **kwargs):
 """ Overridden function to generate the SELECT part of the SQL statement, with the addition of the a modifier if present. """

        return 'SELECT {distinct}{modifier}{select}'.format(
              distinct='DISTINCT ' if self._distinct else '',
              modifier='{} '.format(' '.join(self._modifiers)) if self._modifiers else '',
              select=','.join(term.get_sql(with_alias=True, subquery=True, **kwargs)
                              for term in self._selects),
        )