Sample code below

import re

regex = r'DELETE\s*(?P<table_alias>[a-zA-z_0-9]*)\s*FROM\s*(?P<table_name>[a-zA-z_0-9]+)\s*([a-zA-Z0-9_]*)\s*(?P<where_statement>WHERE){0,1}(\s.)*?'

test_str = 'DELETE FROM my_table1 t_ WHERE id in (1,2,3)'

matches = re.finditer(regex, test_str, re.MULTILINE)

print([m.groupdict() for m in matches])

Below is the expected output.

[{'table_alias': '', 'table_name': 'my_table1', 'where_statement': 'WHERE'}]

But in Win Server 2012 R2, the output is
[{'table_alias': '', 'table_name': 'mytable1', 'where_statement': None}]

Using 3.7 in Win Server 2012 R2 also the output is not as expected. But in Win 10 and other linux variants, expected output is obtained.