关于PEP 8
PEP 8，Style Guide for Python Code，是Python官方推出编码约定，主要是为了保证 Python 编码的风格一致，提高代码的可读性。
官网地址：https://www.python.org/dev/peps/pep-0008/
关于Autopep8
Autopep8是自动将Python代码格式化为符合PEP 8风格的工具。它使用pycodestyle工具来确定代码的哪些部分需要被格式化。Autopep8能够修复大部分pycodestyle检测的格式问题。
github地址：https://github.com/hhatto/autopep8
安装：
pip install autopep8
使用命令：
autopep8 --in-place --aggressive --aggressive <filename>
参数说明：
>usage: autopep8 [-h] [--version] [-v] [-d] [-i] [--global-config filename]> [--ignore-local-config] [-r] [-j n] [-p n] [-a]> [--experimental] [--exclude globs] [--list-fixes]> [--ignore errors] [--select errors] [--max-line-length n]> [--line-range line line]> [files [files ...]]>> Automatically formats Python code to conform to the PEP 8 style guide.>> positional arguments:> files files to format or '-' for standard in>> optional arguments:> -h, --help show this help message and exit> --version show program's version number and exit> -v, --verbose print verbose messages; multiple -v result in more> verbose messages> -d, --diff print the diff for the fixed source> -i, --in-place make changes to files in place> --global-config filename> path to a global pep8 config file; if this file does> not exist then this is ignored (default:> ~/.config/pep8)> --ignore-local-config> don't look for and apply local config files; if not> passed, defaults are updated with any config files in> the project's root directory> -r, --recursive run recursively over directories; must be used with> --in-place or --diff> -j n, --jobs n number of parallel jobs; match CPU count if value is> less than 1> -p n, --pep8-passes n> maximum number of additional pep8 passes (default:> infinite)> -a, --aggressive enable non-whitespace changes; multiple -a result in> more aggressive changes> --experimental enable experimental fixes> --exclude globs exclude file/directory names that match these comma-> separated globs> --list-fixes list codes for fixes; used by --ignore and --select> --ignore errors do not fix these errors/warnings (default: E24)> --select errors fix only these errors/warnings (e.g. E4,W)> --max-line-length n set maximum allowed line length (default: 79)> --line-range line line, --range line line> only fix errors found within this inclusive range of> line numbers (e.g. 1 99); line numbers are indexed at
