Python ModuleNotFoundError：__main__ 不是包是什么意思？

ModuleNotFoundError: What does it mean __main__ is not a package?

提问by lmiguelvargasf

I am trying to run a module from the console. The structure of my directory is this:

我正在尝试从控制台运行一个模块。我的目录结构是这样的：

I am trying to run the module p_03_using_bisection_search.py, from the problem_set_02directory using:

我正在尝试p_03_using_bisection_search.py从problem_set_02目录中运行模块，使用：

$ python3 p_03_using_bisection_search.py

The code inside p_03_using_bisection_search.pyis:

里面的代码p_03_using_bisection_search.py是：

__author__ = 'm'


from .p_02_paying_debt_off_in_a_year import compute_balance_after


def compute_bounds(balance: float,
                   annual_interest_rate: float) -> (float, float):

    # there is code here, but I have omitted it to save space
    pass


def compute_lowest_payment(balance: float,
                           annual_interest_rate: float) -> float:

    # there is code here, but I have omitted it to save space
    pass    

def main():
    balance = eval(input('Enter the initial balance: '))
    annual_interest_rate = eval(input('Enter the annual interest rate: '))

    lowest_payment = compute_lowest_payment(balance, annual_interest_rate)
    print('Lowest Payment: ' + str(lowest_payment))


if __name__ == '__main__':
    main()

I am importing a function that is in p_02_paying_debt_off_in_a_year.pywhich code is:

我正在导入一个函数，p_02_paying_debt_off_in_a_year.py其中的代码是：

__author__ = 'm'


def compute_balance(balance: float,
                    fixed_payment: float,
                    annual_interest_rate: float) -> float:

    # this is code that has been omitted
    pass


def compute_balance_after(balance: float,
                          fixed_payment: float,
                          annual_interest_rate: float,
                          months: int=12) -> float:

    # Omitted code
    pass


def compute_fixed_monthly_payment(balance: float,
                                  annual_interest_rate: float) -> float:

    # omitted code
    pass


def main():
    balance = eval(input('Enter the initial balance: '))
    annual_interest_rate = eval(
        input('Enter the annual interest rate as a decimal: '))
    lowest_payment = compute_fixed_monthly_payment(balance,
                                                   annual_interest_rate)
    print('Lowest Payment: ' + str(lowest_payment))


if __name__ == '__main__':
    main()

I am getting the following error:

我收到以下错误：

ModuleNotFoundError: No module named '__main__.p_02_paying_debt_off_in_a_year'; '__main__' is not a package

I have no idea how to solve this issue. I have tried adding a __init__.pyfile, but it is still not working.

我不知道如何解决这个问题。我已经尝试添加一个__init__.py文件，但它仍然无法正常工作。

回答by Moses Koledoye

Simply remove the dot for the relative import and do:

只需删除相对导入的点并执行：

from p_02_paying_debt_off_in_a_year import compute_balance_after

回答by hcnhcn012

I have the same issue as you did. I think the problem is that you used relative import in in-package import. There is no __init__.pyin your directory. So just import as Moses answered above.

我和你有同样的问题。我认为问题在于您在in-package import. __init__.py您的目录中没有。因此，只需按照摩西上面的回答进行导入。

The core issue I think is when you import with a dot:

我认为的核心问题是当你用点导入时：

from .p_02_paying_debt_off_in_a_year import compute_balance_after

It is equivalent to:

它相当于：

from __main__.p_02_paying_debt_off_in_a_year import compute_balance_after

where __main__refers to your current module p_03_using_bisection_search.py.

where__main__指的是您当前的模块p_03_using_bisection_search.py。

---

---

Briefly, the interpreter does not know your directory architecture.

简而言之，解释器不知道您的目录架构。

When the interpreter get in p_03.py, the script equals:

当解释器进入时p_03.py，脚本等于：

from p_03_using_bisection_search.p_02_paying_debt_off_in_a_year import compute_balance_after

and p_03_using_bisection_searchdoes not contain any modules or instances called p_02_paying_debt_off_in_a_year.

并且p_03_using_bisection_search不包含任何称为p_02_paying_debt_off_in_a_year.

---

---

So I came up with a cleaner solution without changing python environment valuables (after looking up how requestsdo in relative import):

所以我想出了一个更干净的解决方案，而无需更改 python 环境的值（在查看请求在相对导入中的执行方式之后）：

The main architecture of the directory is:

该目录的主要架构是：

main.py

main.py

setup.py

setup.py

---problem_set_02/

---problem_set_02/

------__init__.py

------__init__.py

------p01.py

------p01.py

------p02.py

------p02.py

------p03.py

------p03.py

Then write in __init__.py:

然后写入__init__.py：

from .p_02_paying_debt_off_in_a_year import compute_balance_after

Here __main__is __init__, it exactly refers to the module problem_set_02.

这里__main__是__init__，它究竟指的是模块problem_set_02。

Then go to main.py:

然后去main.py：

import problem_set_02

import problem_set_02

You can also write a setup.pyto add specific module to the environment.

您还可以编写一个setup.py将特定模块添加到环境中。

回答by Dan Keder

Try to run it as:

尝试将其运行为：

python3 -m p_03_using_bisection_search

python3 -m p_03_using_bisection_search

回答by Gaurav Singh

Hi Please follow below step, you will resolve this problem. If you have created directory and sub-directory then follow below steps and please keep in mind all directory must have __init__.pyto get it recognized as a directory.

您好，请按照以下步骤操作，您将解决此问题。如果您已创建目录和子目录，请按照以下步骤操作，请记住所有目录都必须 __init__.py将其识别为目录。

1. import sysand run sys.path, you will be able to see all path that is being search by python.You must be able to see your current working directory.

2. Now import sub-directory and respective module that you want to use using import follow this command: import subdir.subdir.modulename as abcand now you can use the methods in that module. ScreenShotforSameIssue

1. import sys并运行sys.path，您将能够看到python正在搜索的所有路径。您必须能够看到您当前的工作目录。

2. 现在使用 import 导入子目录和要使用的相应模块，请遵循以下命令：import subdir.subdir.modulename as abc现在您可以使用该模块中的方法。 相同问题的屏幕截图

as you can see in this screenshot I have one parent directory and two sub-directories and under second sub-directories i have module==CommonFunction and you see right side after execution of sys.path I can see my working directory

正如你在这个截图中看到的，我有一个父目录和两个子目录，在第二个子目录下我有 module==CommonFunction，你在执行 sys.path 后看到右侧我可以看到我的工作目录

回答by Aminah Nuraini

Remove the dot and import absolute_import in the beginning of your file

删除点并在文件开头导入 absolute_import

from __future__ import absolute_import

from p_02_paying_debt_off_in_a_year import compute_balance_after

回答by FanBek

Just use the name of the main folder which the .py file is in.

只需使用 .py 文件所在的主文件夹的名称。

from problem_set_02.p_02_paying_debt_off_in_a_year import compute_balance_after