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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 get_number(self, num, table=None):
 """Get a specific entry by its number."""

        if table is None: table = self.main_table
        self.own_cursor.execute('SELECT * from "%s" LIMIT 1 OFFSET %i;' % (self.main_table, num))
        return self.own_cursor.fetchone()