你还可以使用如下语句:

import pip

def install(package):
    if hasattr(pip, 'main'):
        pip.main(['install', package])
    else:
        pip._internal.main(['install', package])

# Example
if __name__ == '__main__':
    install('argh')

    import pip

try:
    import imaplib
    import email
    import pandas as pd
    # for hiding password
    from pathlib import Path
    from dotenv import load_dotenv
    import os
    import requests
    # 
    from collections import defaultdict
    from itertools import permutations,combinations
except Exception as e:
    print(e)
    e = str(e).split(' ')[-1].replace("'","")
    pip.main(['install', e])

你还可以使用如下语句:

import pip

def install(package):
    if hasattr(pip, 'main'):
        pip.main(['install', package])
    else:
        pip._internal.main(['install', package])

# Example
if __name__ == '__main__':
    install('argh')

如果你想使用pip安装所需的包，并在安装后导入，你可以使用这段代码:

def install_and_import(package):
    import importlib
    try:
        importlib.import_module(package)
    except ImportError:
        import pip
        pip.main(['install', package])
    finally:
        globals()[package] = importlib.import_module(package)


install_and_import('transliterate')

如果您以用户身份安装包，可能会遇到不能直接导入包的问题。参见如何刷新sys.path?获取更多信息。

我在@Aaron的回答中添加了一些异常处理。

import subprocess
import sys

try:
    import pandas as pd
except ImportError:
    subprocess.check_call([sys.executable, "-m", "pip", "install", 'pandas'])
finally:
    import pandas as pd

这应该可以工作:

import subprocess

def install(name):
    subprocess.call(['pip', 'install', name])