为什么我的导入可以在pycharm中工作，但不能在命令行上工作？

我有以下文件夹布局：

my_folder/
    my_subfolder/
        __init__.py
        main.py
        import_1.py
        import_2.py

带有文件：

 # main.py
 from my_subfolder import import_1

 import_1.call_import_2(3)

和

 # import_1.py
 from my_subfolder import import_2

 def call_import_2(n):
     import_2.print_hello_world_n_times(n)

和

# import_2.py

def print_hello_world_n_times(n):
    for i in range(n):
        print('hello world')

Now the thing is, if I run main.py in pycharm, it works fine. However, if I run it from the command line python my_subfolder/main.py or python main.py (depending which folder I am in), it doesn't work! The git bash also cannot get it to work. I get the error:

ModuleNotFoundError no module named 'my_subfolder'

有谁知道是什么原因导致pycharm和命令行之间出现此差异？