python - ImportError : cannot import name 'Mapping' from 'collections' , flask 导入不工作

Question

今天我尝试导入一个库存管理 flask 应用程序，但我遇到了很多错误。希望你能帮助我这个项目，它来自 github https://github.com/marination/Inventory-Manager

这些是错误:

Traceback (most recent call last):
File "C:\workspace\Inventory-Manager\run.py", line 1, in <module>
from flaskinventory import app
File "C:\workspace\Inventory-Manager\flaskinventory\__init__.py", line 1, in <module>
from flask import Flask
File "C:\workspace\Inventory-Manager\ven\lib\site-packages\flask\__init__.py", line 19, in  <module>
from jinja2 import Markup, escape
File "C:\workspace\Inventory-Manager\ven\lib\site-packages\jinja2\__init__.py", line 33, in  <module>
from jinja2.environment import Environment, Template
File "C:\workspace\Inventory-Manager\ven\lib\site-packages\jinja2\environment.py", line 16, in <module>
from jinja2.defaults import BLOCK_START_STRING, \
File "C:\workspace\Inventory-Manager\ven\lib\site-packages\jinja2\defaults.py", line 32, in  <module>
from jinja2.tests import TESTS as DEFAULT_TESTS
File "C:\workspace\Inventory-Manager\ven\lib\site-packages\jinja2\tests.py", line 13, in  <module>
from collections import Mapping
ImportError: cannot import name 'Mapping' from 'collections' 
(C:\Python310\lib\collections\__init__.py)

Answer 1

collections.Mapping 自 Python 3.3 以来已被弃用，并已从 Python 3.10 中的 collections 模块中删除。在 Python 3.3 - 3.9 中，您应该会看到类似以下的警告:

DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated since Python 3.3, and in 3.10 it will stop working

需要为 Python 3.10 更新这些导入以从 collections.abc 导入 Mapping

在这种情况下，导入发生在 jinja2 中。要解决此问题，请使用修复此问题的 jinja2 更新版本或使用 Python 3.9 或更早版本。