TypeError: argument of type 'NoneType' is not iterable

[ivbeg]

Describe the bug
TypeError argument of type 'NoneType' is not iterable

To Reproduce
Steps to reproduce the behavior:

1. Take file https://github.com/centreon/centreon-broker/blob/aae49ea83a14c74885935f4e8058eefbadc24abd/test/mysql_v2/timeperiod_exceptions.sql?raw=True
2. Use code ddl = parse_from_file(filepath)
3. See error TypeError argument of type 'NoneType' is not iterable

Expected behavior
DDLParserError with a clear error explanation

More examples

• https://github.com/1020528175/iBase4J/blob/09732918743732bf7e4af539e0871809f2a809c6/iBase4J-UI/iBase4J-UI-DataTables/sql/3.quartz.mysql.sql?raw=True
• https://github.com/DAINTINESS-Group/Schema_Evolution_Datasets/blob/9a5b20bd52424fc31e41d22c50f3847e1c7574ad/SchemaEvolutionDatasets2017/CMS's/wikimedia/2017_collection/schemata/master/1230747050.sql?raw=True
• https://github.com/dalinaum/kakao-mariadb/blob/cfcfa5ff636d7a01e7f07e8a0ed83654bc979df6/mysql-test/include/mix1.inc?raw=True
• https://github.com/ksourav796/RestoposLite/blob/27c3838a04e0a18abb984d838de20bf6aab28a03/target/classes/tables_mysql_innodb.sql?raw=True

[xnuinside]

TypeError argument of type 'NoneType' is not iterable - fixed in 0.29.0 (at lease for the first query sample), test added here - https://github.com/xnuinside/simple-ddl-parser/blob/main/tests/test_references.py#L395

But, I will not close the issue because of another problems in samples )