pipenv是pip和virtualenv的合体，用来管理python环境，因为是在国内使用，建议替换成国内源,参考地址 ：
默认python源： https://pypi.org/simple
使用需要先安装python、pip和pipenv，请自行百度，安装完成后，进行pipenv安装
pip install pipenv
经常出现下载慢或者链接超时的问题，请使用windows系统的童鞋修改源：
（1）：在windows文件管理器中,输入 %APPDATA%
（2）：会定位到一个新的目录下，在该目录下新建pip文件夹，然后到pip文件夹里面去新建个pip.ini文件
（3）：在新建的pip.ini文件中输入以下内容，搞定文件路 径："C:\Users\Administrator\AppData\Roaming\pip\pip.ini"
[global]
index-url = https://pypi.doubanio.com/simple
[install]
trusted-host = pypi.doubanio.com
用法
1、打开终端(cmder/terminal)，进入到项目根目录下，执行
pipenv install #默认环境变量里配置的python版本
pipenv --python path-to-python #指定python版本安装虚拟环境，也可用 pipenv --three
2、进入虚拟环境，安装各种依赖包：
pipenv shell
pipenv install -r requirements.txt #项目之前使用requirements.txt管理包，可以切换一下
PS：具体使用命令不一一详解，请参考:
(practice_floder-FsVo9ztC) λ pipenv -h
Usage: pipenv [OPTIONS] COMMAND [ARGS]...
Options:
--where Output project home information.
--venv Output virtualenv information.
--py Output Python interpreter information.
--envs Output Environment Variable options.
--rm Remove the virtualenv.
--bare Minimal output.
--completion Output completion (to be eval'd).
--man Display manpage.
--support Output diagnostic information for use in GitHub issues.
--site-packages Enable site-packages for the virtualenv. [env var:
PIPENV_SITE_PACKAGES]
--python TEXT Specify which version of Python virtualenv should use.
--three / --two Use Python 3/2 when creating virtualenv.
--clear Clears caches (pipenv, pip, and pip-tools). [env var:
PIPENV_CLEAR]
-v, --verbose Verbose mode.
--pypi-mirror TEXT Specify a PyPI mirror.
--version Show the version and exit.
-h, --help Show this message and exit.
Usage Examples:
Create a new project using Python 3.7, specifically:
$ pipenv --python 3.7
Remove project virtualenv (inferred from current directory):
$ pipenv --rm
Install all dependencies for a project (including dev):
$ pipenv install --dev
Create a lockfile containing pre-releases:
$ pipenv lock --pre
Show a graph of your installed dependencies:
$ pipenv graph
Check your installed dependencies for security vulnerabilities:
$ pipenv check
Install a local setup.py into your virtual environment/Pipfile:
$ pipenv install -e .
Use a lower-level pip command:
$ pipenv run pip freeze
Commands:
check Checks for security vulnerabilities and against PEP 508 markers
provided in Pipfile.
clean Uninstalls all packages not specified in Pipfile.lock.
graph Displays currently-installed dependency graph information.
install Installs provided packages and adds them to Pipfile, or (if no
packages are given), installs all packages from Pipfile.
lock Generates Pipfile.lock.
open View a given module in your editor.
run Spawns a command installed into the virtualenv.
shell Spawns a shell within the virtualenv.
sync Installs all packages specified in Pipfile.lock.
uninstall Un-installs a provided package and removes it from Pipfile.
update Runs lock, then sync.
常见问题：
pipenv.patched.notpip._vendor.urllib3.exceptions.ReadTimeoutError:
HTTPSConnectionPool(host='files.pythonhosted.org', port=443): Read timed out.
