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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 delete(self, table, where=None):
 """Delete existing rows from a table."""

        if where:
            where_key, where_val = where
            query = "DELETE FROM {0} WHERE {1}='{2}'".format(wrap(table), where_key, where_val)
        else:
            query = 'DELETE FROM {0}'.format(wrap(table))
        self.execute(query)
        return True