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Remove unnecessary tz_bytes variable.

Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>

Author: fatihhcelik

Lib/zoneinfo/_common.py

@@ -118,13 +118,10 @@ def get_abbr(idx):
         c = fobj.read(1)  # Should be \n
         assert c == b"\n", c
 
-        tz_bytes = b""
         line = fobj.readline()
         if not line.endswith(b"\n"):
             raise ValueError("Invalid TZif file: unexpected end of file")
-        tz_bytes = line.rstrip(b"\n")
-
-        tz_str = tz_bytes
+        tz_str = line.rstrip(b"\n")
     else:
         tz_str = None