diff --git a/split.py b/split.py
index 4d8b307417..d3682ef42d 100755
--- a/split.py
+++ b/split.py
@@ -2,66 +2,72 @@
 
 """This script splits httplib.h into .h and .cc parts."""
 
-import argparse
 import os
 import sys
+from argparse import ArgumentParser, Namespace
+from typing import List
 
-border = '// ----------------------------------------------------------------------------'
 
-args_parser = argparse.ArgumentParser(description=__doc__)
-args_parser.add_argument(
-    "-e", "--extension", help="extension of the implementation file (default: cc)",
-    default="cc"
-)
-args_parser.add_argument(
-    "-o", "--out", help="where to write the files (default: out)", default="out"
-)
-args = args_parser.parse_args()
+def main() -> None:
+    """Main entry point for the script."""
+    BORDER: str = '// ----------------------------------------------------------------------------'
 
-cur_dir = os.path.dirname(sys.argv[0])
-lib_name = 'httplib'
-header_name = '/' + lib_name + '.h'
-source_name = '/' + lib_name + '.' + args.extension
-# get the input file
-in_file = cur_dir + header_name
-# get the output file
-h_out = args.out + header_name
-cc_out = args.out + source_name
+    args_parser: ArgumentParser = ArgumentParser(description=__doc__)
+    args_parser.add_argument(
+        "-e", "--extension", help="extension of the implementation file (default: cc)",
+        default="cc"
+    )
+    args_parser.add_argument(
+        "-o", "--out", help="where to write the files (default: out)", default="out"
+    )
+    args: Namespace = args_parser.parse_args()
 
-# if the modification time of the out file is after the in file,
-# don't split (as it is already finished)
-do_split = True
+    cur_dir: str = os.path.dirname(sys.argv[0])
+    if not cur_dir:
+        cur_dir = '.'
+    lib_name: str = 'httplib'
+    header_name: str = f"/{lib_name}.h"
+    source_name: str = f"/{lib_name}.{args.extension}"
+    # get the input file
+    in_file: str = cur_dir + header_name
+    # get the output file
+    h_out: str = args.out + header_name
+    cc_out: str = args.out + source_name
 
-if os.path.exists(h_out):
-    in_time = os.path.getmtime(in_file)
-    out_time = os.path.getmtime(h_out)
-    do_split = in_time > out_time
+    # if the modification time of the out file is after the in file,
+    # don't split (as it is already finished)
+    do_split: bool = True
 
-if do_split:
-    with open(in_file) as f:
-        lines = f.readlines()
+    if os.path.exists(h_out):
+        in_time: float = os.path.getmtime(in_file)
+        out_time: float = os.path.getmtime(h_out)
+        do_split: bool = in_time > out_time
+
+    if do_split:
+        with open(in_file) as f:
+            lines: List[str] = f.readlines()
 
-    python_version = sys.version_info[0]
-    if python_version < 3:
-        os.makedirs(args.out)
-    else:
         os.makedirs(args.out, exist_ok=True)
 
-    in_implementation = False
-    cc_out = args.out + source_name
-    with open(h_out, 'w') as fh, open(cc_out, 'w') as fc:
-        fc.write('#include "httplib.h"\n')
-        fc.write('namespace httplib {\n')
-        for line in lines:
-            is_border_line = border in line
-            if is_border_line:
-                in_implementation = not in_implementation
-            elif in_implementation:
-                fc.write(line.replace('inline ', ''))
-            else:
-                fh.write(line)
-        fc.write('} // namespace httplib\n')
+        in_implementation: bool = False
+        cc_out: str = args.out + source_name
+        with open(h_out, 'w') as fh, open(cc_out, 'w') as fc:
+            fc.write('#include "httplib.h"\n')
+            fc.write('namespace httplib {\n')
+            for line in lines:
+                is_border_line: bool = BORDER in line
+                if is_border_line:
+                    in_implementation: bool = not in_implementation
+                elif in_implementation:
+                    fc.write(line.replace('inline ', ''))
+                else:
+                    fh.write(line)
+            fc.write('} // namespace httplib\n')
+
+        print(f"Wrote {h_out} and {cc_out}")
+    else:
+        print(f"{h_out} and {cc_out} are up to date")
+
 
-    print("Wrote {} and {}".format(h_out, cc_out))
-else:
-    print("{} and {} are up to date".format(h_out, cc_out))
+if __name__ == "__main__":
+    main()