chgserver: remove Python 2 file descriptor logic
Follows up
0bb28b7736bc "chgserver: remove Python 2 support code."
On Python 2, we had to close newfp prior to restoring the original file
description since "delete newfp" would otherwise close the file descriptor
shared with the long-lived fp:
in attachio():
newfp = os.fdopen(fp.fileno(), mode, bufsize)
in _restoreio():
newfp.close() # temporarily close newfp.fileno() (= fp.fileno())
os.dup2(fd, fp.fileno()) # reopen fp.fileno() with original fd
On the other hand, we shouldn't call newfp.close() on Python 3 since
any function calls are proxied to the underlying file object by
procutil.LineBufferedWrapper.
[build-system]
requires = ["setuptools", "wheel"]
[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
'''
skip-string-normalization = true
quiet = true