Antlr4 python runtime error after generating from grammar

I using the following Antlr4 PLSQL grammar files:

https://github.com/antlr/grammars-v4/tree/master/sql/plsql.

From here I downloaded as follows:

wget https://github.com/antlr/grammars-v4/blob/master/sql/plsql/Python3/PlSqlLexerBase.pywget https://github.com/antlr/grammars-v4/blob/master/sql/plsql/Python3/PlSqlParserBase.pywget https://github.com/antlr/grammars-v4/blob/master/sql/plsql/PlSqlLexer.g4wget https://github.com/antlr/grammars-v4/blob/master/sql/plsql/PlSqlParser.g4mv PlSql*g4 grammarswget https://www.antlr.org/download/antlr-4.13.1-complete.jarmv antlr-4.13.1-complete.jar lib

Giving me :

├── lib│  ├── antlr-4.13.1-complete.jar├── grammars1│  ├── PlSqlLexer.g4│  └── PlSqlParser.g4├── PlSqlLexer.g4├── PlSqlParser.py

When I then run:

java -jar ./lib/antlr-4.9.3-complete.jar -Dlanguage=Python3 grammars/*g4

I get the following generated in grammars:

grammars-v4-master  PlSqlLexer.interp  PlSqlParserBase.py  PlSqlParserListener.py  __pycache__master.zip          PlSqlLexer.py      PlSqlParser.g4      PlSqlParser.py          runPLSQL.pyPlSqlLexer.g4       PlSqlLexer.tokens  PlSqlParser.interp  PlSqlParser.tokens

I then create the runPLSQL.py Python script :

cd grammarspython3 runPLSQL.py ../../plsql/test.sql

But this errored with:

  import pandasTraceback (most recent call last):  File "/home/me/try2/grammars/runPLSQL.py", line 11, in <module>    from PlSqlParserListener import PlSqlParserListener  File "/home/me/try2/grammars/PlSqlParserListener.py", line 6, in <module>    from PlSqlParser import PlSqlParser  File "/home/me/try2/grammars/PlSqlParser.py", line 14, in <module>    from PlSqlParserBase import PlSqlParserBase  File "/home/me/try2/grammars/PlSqlParserBase.py", line 1, in <module>    {"payload":{"allShortcutsEnabled":false,"fileTree":{"sql/plsql/Python3":{"items":[{"name":"PlSqlLexerBase.py","path":"sql/plsql/Python3/PlSqlLexerBase.py","contentType":"file"}NameError: name 'false' is not defined. Did you mean: 'False'?

I had to edit the PlSqlLexerBase.py file as below to overcome this and similar errors:

1. Replace :false with :False
2. Replace :true with :True
3. Replace :null with :None

But now I get this:

  import pandasTraceback (most recent call last):  File "/home/me/try2/grammars/runPLSQL.py", line 11, in <module>    from PlSqlParserListener import PlSqlParserListener  File "/home/me/try2/grammars/PlSqlParserListener.py", line 6, in <module>    from PlSqlParser import PlSqlParser  File "/home/me/try2/grammars/PlSqlParser.py", line 14, in <module>    from PlSqlParserBase import PlSqlParserBaseImportError: cannot import name 'PlSqlParserBase' from 'PlSqlParserBase' (/home/me/try2/grammars/PlSqlParserBase.py)

The PlSqlParserBase.py script starts with:

{"payload":{"allShortcutsEnabled":False,"fileTree":{"sql/plsql/Python3":{"items":[{"name":"PlSqlLexerBase.py","path":"sql/plsql/Python3/PlSqlLexerBase.py","contentType":"file"},{"name":"PlSqlParserBase.py","path":"sql/plsql/Python3/PlSqlParserBase.py","contentType":"file"}],"totalCount":2},"sql/plsql":{"items":[{"name":"CSharp","path":"sql/plsql/CSharp","contentTy......

I notice it references relative pathnames, should all the paths/files exist?

The top of the runPLSQL.py script is:

import osimport pandasfrom antlr4 import InputStream, ParseTreeWalkerfrom antlr4.CommonTokenStream import CommonTokenStreamfrom pandas import DataFrame#from PlSql.grammar.PlSqlListener import PlSqlListener#from PlSql.grammar.PlSqlLexer import PlSqlLexer#from PlSql.grammar.PlSqlParser import PlSqlParserfrom PlSqlParserListener import PlSqlParserListenerfrom PlSqlLexer import PlSqlLexerfrom PlSqlParser import PlSqlParserfrom tabulate import tabulateclass SQLParser(PlSqlListener):