python模块内置变量及其作用

1.__file__

所在模块：os

变量作用：指向当前文件

当前文件的完整路径：os.path.abspath(__file__)

当前文件所属目录：os.path.dirname(os.path.abspath(__file__))

当前文件所属目录的上级目录：os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

cat filelocation.py
import os
print(__file__)
print(os.path.abspath("filelocation.py"))
print(os.path.abspath(__file__))
print(os.path.dirname(os.path.abspath(__file__)))
print(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
运行：
filelocation.py
/home/test/CodeProjects/PythonProjects/test/filelocation.py
/home/test/CodeProjects/PythonProjects/test/filelocation.py
/home/test/CodeProjects/PythonProjects/test
/home/test/CodeProjects/PythonProjects