无法为 Flask 应用安装 pg_config

Can't install pg_config for flask app

我是运行下面的命令

pip install -r .\requirements.txt

在项目目录下得到如下错误

Using cached psycopg2-2.5.3.tar.gz
Complete output from command python setup.py egg_info:
running egg_info
creating pip-egg-info\psycopg2.egg-info
writing pip-egg-info\psycopg2.egg-info\PKG-INFO
writing top-level names to pip-egg-info\psycopg2.egg-info\top_level.txt
writing dependency_links to pip-egg-info\psycopg2.egg-info\dependency_links.txt
writing manifest file 'pip-egg-info\psycopg2.egg-info\SOURCES.txt'
warning: manifest_maker: standard file '-c' not found

Error: pg_config executable not found.

Please add the directory containing pg_config to the PATH
or specify the full executable path with the option:

    python setup.py build_ext --pg-config /path/to/pg_config build ...

or with the pg_config option in 'setup.cfg'.

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命令 "python setup.py egg_info" 在 c:\users\eugene~1\appdata\local\temp\pip-build-mil943\psy 中失败,错误代码为 1 copg2

C:\Program Files\PostgreSQL.4\bin 必须在环境路径