Issue #16304: Further optimize BZ2File.readlines?().

Lib/bz2.py

@@ -319,6 +319,7 @@ class BZ2File(io.BufferedIOBase):
         non-negative, no more than size bytes will be read (in which
         case the line may be incomplete). Returns b'' if already at EOF.
         """
+        if not isinstance(size, int):
             if not hasattr(size, "__index__"):
                 raise TypeError("Integer argument expected")
             size = size.__index__()
@@ -341,6 +342,7 @@ class BZ2File(io.BufferedIOBase):
         further lines will be read once the total size of the lines read
         so far equals or exceeds size.
         """
+        if not isinstance(size, int):
             if not hasattr(size, "__index__"):
                 raise TypeError("Integer argument expected")
             size = size.__index__()