style: pre-commit fixes

Author: pre-commit-ci[bot]

src/uproot/compression.py

@@ -94,7 +94,7 @@ def decompress(self, data: bytes, uncompressed_bytes=None) -> bytes:
             raise ValueError(
                 "zlib decompression requires the number of uncompressed bytes"
             )
-        
+
         if self.library == "zlib":
             import zlib
 
@@ -621,10 +621,8 @@ def compress(data: bytes, compression: Compression) -> bytes:
     format (bytes, memoryview, or NumPy array) it was provided.
     """
 
-    def _normalize_bytes(x):
-        if isinstance(x, list):
-            return b"".join(x)
-        return x
+    if compression is None or compression.level == 0:
+        return data
 
     out = []
     next = data