Manual fixes to Python file

To see if I like the rules

hm/dev/pythonstartup.py

@@ -1,7 +1,6 @@
-#!/usr/bin/env python3
-
-import os
-import sys
+import sys  # noqa: I001
+import contextlib
+import pathlib
 
 
 # From https://github.com/python/cpython/blob/v3.7.0b5/Lib/site.py#L436
@@ -11,7 +10,7 @@ def register_readline() -> None:
 
     try:
         import readline
-        import rlcompleter
+        import rlcompleter  # noqa: F401
     except ImportError:
         return
 
@@ -23,14 +22,13 @@ def register_readline() -> None:
     else:
         readline.parse_and_bind("tab: complete")
 
-    try:
+    # An OSError here could have many causes, but the most likely one
+    # is that there's no .inputrc file (or .editrc file in the case of
+    # Mac OS X + libedit) in the expected location.  In that case, we
+    # want to ignore the exception.
+    cm = contextlib.suppress(OSError)
+    with cm:
         readline.read_init_file()
-    except OSError:
-        # An OSError here could have many causes, but the most likely one
-        # is that there's no .inputrc file (or .editrc file in the case of
-        # Mac OS X + libedit) in the expected location.  In that case, we
-        # want to ignore the exception.
-        pass
 
     if readline.get_current_history_length() == 0:
         # If no history was loaded, default to .python_history.
@@ -38,14 +36,11 @@ def register_readline() -> None:
         # each interpreter exit when readline was already configured
         # through a PYTHONSTARTUP hook, see:
         # http://bugs.python.org/issue5845#msg198636
-        history = os.path.join(
-            os.path.expanduser("~"), ".cache/python_history"
-        )
-        try:
+        history = pathlib.Path("~/.cache/python_history").expanduser()
+        cm = contextlib.suppress(OSError)
+        with cm:
             readline.read_history_file(history)
-        except OSError:
-            pass
         atexit.register(readline.write_history_file, history)
 
 
-sys.__interactivehook__ = register_readline
+sys.__interactivehook__ = register_readline  # noqa: attr-defined