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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_as_dict(self, table_name, columns=None, where=None, extra=None):
 """ Get data in the database and return fetched data as a |OrderedDict| list. :param str table_name: |arg_select_table_name| :param list columns: |arg_select_as_xx_columns| :param where: |arg_select_where| :type where: |arg_where_type| :param str extra: |arg_select_extra| :return: Table data as |OrderedDict| instances. :rtype: |list| of |OrderedDict| :raises simplesqlite.NullDatabaseConnectionError: |raises_check_connection| :raises simplesqlite.TableNotFoundError: |raises_verify_table_existence| :raises simplesqlite.OperationalError: |raises_operational_error| :Example: :ref:`example-select-as-dict` """


        return self.select_as_tabledata(table_name, columns, where, extra).as_dict().get(table_name)