[compat] Split into sub-modules (#2173)

Authored by: fstirlitz, pukkandan

yt_dlp/webvtt.py

@@ -9,9 +9,8 @@ in RFC 8216 §3.5 <https://tools.ietf.org/html/rfc8216#section-3.5>.
 """
 
 import io
-import re
 
-from .compat import compat_Match, compat_Pattern
+from .compat import re
 from .utils import int_or_none, timetuple_from_msec
 
 
@@ -26,7 +25,7 @@ class _MatchParser:
         self._pos = 0
 
     def match(self, r):
-        if isinstance(r, compat_Pattern):
+        if isinstance(r, re.Pattern):
             return r.match(self._data, self._pos)
         if isinstance(r, str):
             if self._data.startswith(r, self._pos):
@@ -37,7 +36,7 @@ class _MatchParser:
     def advance(self, by):
         if by is None:
             amt = 0
-        elif isinstance(by, compat_Match):
+        elif isinstance(by, re.Match):
             amt = len(by.group(0))
         elif isinstance(by, str):
             amt = len(by)