Returns the SQL command for creating a table for this model.

def create_table_sql(cls, db):
        '''
        Returns the SQL command for creating a table for this model.
        '''
        parts = ['CREATE TABLE IF NOT EXISTS `%s`.`%s` (' % (db.db_name, cls.table_name())]
        cols = []
        for name, field in iteritems(cls.fields()):
            cols.append('    %s %s' % (name, field.get_sql()))
        parts.append(',\n'.join(cols))
        parts.append(')')
        parts.append('ENGINE = ' + cls.engine.create_table_sql(db))
        return '\n'.join(parts)