07-16 importlib模块

作用: 通过字符串'包.包.模块'这种形式导入模块

import importlib

module_str = 'concurrent.futures'
# 注意: 该方法最小只能到py文件名(模块)
res = importlib.import_module(module_str)    # 等同于 -> from concurrent import futures
print(res)   # <module 'concurrent.futures' from 'Y:\\python-3.6.3\\installation-site\\lib\\concurrent\\futures\\__init__.py'>