Python 在uuu init_uuuuuuuuuu.py和`import as`语句中导入_Python_Python 3.x

Python 在uuu init_uuuuuuuuuu.py和`import as`语句中导入

python python-3.x

Python 在uuu init_uuuuuuuuuu.py和`import as`语句中导入,python,python-3.x,Python,Python 3.x,我遇到了一个问题，在\uuu init\uuuu.py中有导入，并且在包的模块中使用导入为我的项目有一个子包，在它的\uuuu init\uuuuuu.py中，我使用从导入为语句将一个类从模块“提升”到子包级别。模块使用绝对导入从该子包导入其他模块。我得到这个错误AttributeError:“module”对象没有属性“subpkg” 例子结构： pkg/ ├── __init__.py ├── subpkg │ ├── __init__.py │ ├── one.py │ └

我遇到了一个问题，在

\uuu init\uuuu.py

中有导入，并且在包的模块中使用

导入为

我的项目有一个子包，在它的

\uuuu init\uuuuuu.py

中，我使用

从导入为语句将一个类从模块“提升”到子包级别。模块使用绝对导入从该子包导入其他模块。我得到这个错误AttributeError:“module”对象没有属性“subpkg”

例子
结构：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

pkg/\uuuu init\uuuu.py为空
pkg/subpkg/__;u init.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

pkg/subkg/one.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

pkg/subpkg/two_longname.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

包装/tst.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

输出：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

这里唯一的缺点是我不能为模块创建短别名。我从@begueradj的回答中得到了这个想法
也可以在one.py
中使用相对导入来解决问题。但我认为这只是变通办法2的一种变体
问题
有人能解释一下这里到底发生了什么吗？为什么在\uuu init\uuuu.py
中同时导入和使用导入为
会导致此类问题
有更好的解决办法吗

原样
这是我最初的例子。这不太现实，但我不会删除它，所以@begueradj的答案仍然有意义
pkg/\uuuu init\uuuu.py为空
pkg/subpkg/__;u init.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

pkg/subkg/one.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

pkg/subkg/two.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

包装/tst.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

输出：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two_longname.py
└── tst.py

from pkg.subpkg.one import One

import pkg.subpkg.two_longname as two

class One(two.Two):
    pass

class Two:
    pass

from pkg.subpkg import One

print(One)

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest2/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/__init__.py", line 1, in <module>
    from pkg.subpkg.one import One
  File "/home/and/dev/test/python/imptest2/pkg/subpkg/one.py", line 1, in <module>
    import pkg.subpkg.two_longname as two
AttributeError: 'module' object has no attribute 'subpkg'

from pkg.subpkg.one import ONE

import pkg.subpkg.two
ONE = pkg.subpkg.two.TWO

TWO = 2

from pkg.subpkg import ONE

$ python3.4 -m pkg.tst
Traceback (most recent call last):
  File "/usr/lib/python3.4/runpy.py", line 170, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.4/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/home/and/dev/test/python/imptest/pkg/tst.py", line 1, in <module>
    from pkg.subpkg import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/__init__.py", line 2, in <module>
    from pkg.subpkg.one import ONE
  File "/home/and/dev/test/python/imptest/pkg/subpkg/one.py", line 6, in <module>
    ONE = pkg.subpkg.two.TWO
AttributeError: 'module' object has no attribute 'subpkg'

import pkg.subpkg.two as two
ONE = two.TWO

在这种情况下，我在导入时出错（就像在我的原始项目中一样，它也使用导入为。
关于调用模块的方式，您的项目结构必须如下所示：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two.py
tst.py

class TWO:
    def functionTwo(self):
        print("2")

如下定义您的two.py：
pkg/
├── __init__.py
├── subpkg
│   ├── __init__.py
│   ├── one.py
│   └── two.py
tst.py

class TWO:
    def functionTwo(self):
        print("2")

如下定义您的one.py：
from pkg.subpkg import two
class ONE:
    def functionOne(self):
        print("1")

        self.T=two.TWO()
        print("Calling TWO from ONE: ")
        self.T.functionTwo()

像这样定义您的test.py
from pkg.subpkg import one
class TEST:
    def functionTest(self):
        O=one.ONE()
        O.functionOne()
if __name__=='__main__':
    T=TEST()
    T.functionTest()

执行时，您将得到以下结果：
1
Calling  TWO from  ONE:
2

希望这能有所帮助。
这里有一个关于发生了什么的理论
当您将用作
保留字时，例如：
import pkg.subpkg.two_longname as two

Python必须完全初始化并解决与pkg.subpkg
有关的所有依赖关系。但是有一个问题，要完全加载subkg
，您还需要完全加载one.py，对吗？wich同时使用as
关键字导入two_longname.py
。。。你能看到这里的递归吗？这就是为什么在做这件事的时候：
import pkg.subpkg.two_longname as two

您会收到一个错误，声称subpkg
不存在
要执行测试，请转到one.py并将其更改为：
#import pkg.subpkg.two_longname as two
from pkg.subpkg import two_longname

#class One(two.Two):
class One(two_longname.Two):
    pass

我想这都是关于性能的，只要有可能，Python就会部分加载模块。而as
关键字是例外情况之一。我不知道是否还有其他人，但了解他们会很有趣。
您错误地认为一个人不能有来自的别名。。。从…导入
，作为。。。导入。。。自Python 2.0以来，as一直存在。导入。。。as
是一种晦涩难懂的语法，不是很多人都知道，但您在代码中意外地使用了它
声称以下2项“实际上”相同：
将foo.bar.bazaar导入为baz
来自foo.bar进口商场作为baz
这句话在3.6.x之前（含3.6.x）的Python版本中并不完全正确，正如您遇到的一个案例所证明的，即如果所需的模块已经存在于sys.modules
中，但尚未初始化。导入。。。as
要求模块foo.bar
作为属性bar
插入foo.bar
命名空间中，除了位于sys.modules
中之外，而来自。。。导入。。。as
在sys.modules
中查找foo.bar

（请注意，import foo.bar
仅确保模块foo.bar
位于sys.modules
中，并且可以作为foo.bar
访问，但可能尚未完全初始化。）
按以下方式更改代码为我带来了好处：
# import pkg.subpkg.two_longname as two
from pkg.subpkg import two_longname as two

代码在Python2和Python3上都能完美运行
此外，出于同样的原因，在one.py
中，您不能从pkg import subkg执行

要进一步演示此错误，请如上所述修复one.py
，并在tst.py
中添加以下代码：
from pkg.subpkg import two_longname

class One(two_longname.Two):
    pass

import pkg
import pkg.subpkg.two_longname as two

del pkg.subpkg

from pkg.subpkg import two_longname as two
import pkg.subpkg.two_longname as two

只有最后一行崩溃，因为来自。。。import
为pkg.subpkg
查询sys.modules
，并在那里找到它，而import。。。as
为pkg
查阅sys.modules
，并尝试在pkg
模块中作为属性查找subpkg
。由于我们刚刚删除了该属性，最后一行失败，出现了AttributeError:“module”对象没有属性“subpkg”


由于import foo.bar As baz
语法有点晦涩，并且添加了更多的角格，而且我很少看到它被使用，因此我建议完全避免使用它，并从中选择。。导入。。。正如公认的答案所说，这是Python行为的一个问题
我提出了一个错误：
Serhiy Storchaka的修复是在Python 3.7中合并的，我的理解是，将导入内容的使用转移到函数中会有所帮助，因为它允许Python先导入所有内容，然后开始使用它。然而，这并不总是可能做到的。例如，导入一个超类。也许我应该将我的示例建立在这个案例的基础上，使其更加真实。另外，我注意到您使用了from pkg.subpkg import two
而不是将pkg.subpkg.two导入为two
。这