Pylint: False positive E0611/E0401 (No Name / Unable to Import)

[jrial]

In my code I have the following imports:

import email
from email.MIMEBase import MIMEBase
from email.MIMEMultipart import MIMEMultipart
from email.MIMEText import MIMEText

And further in the code:

        output = u''.join(
            txt.decode(enc or 'iso8859-1') if isinstance(txt, bytes) else txt
            for txt, enc in email.Header.decode_header(word)
        )

and

email.Encoders.encode_base64(out_message_attachment)

When I run Pylint over this file, I get the following errors:

[E0611] maileater/models.py:4:0 : No name 'MIMEBase' in module 'email'
[E0401] maileater/models.py:4:0 : Unable to import 'email.MIMEBase'
[E0611] maileater/models.py:5:0 : No name 'MIMEMultipart' in module 'email'
[E0401] maileater/models.py:5:0 : Unable to import 'email.MIMEMultipart'
[E0611] maileater/models.py:6:0 : No name 'MIMEText' in module 'email'
[E0401] maileater/models.py:6:0 : Unable to import 'email.MIMEText'
[E1101] maileater/models.py:55:28 : Module 'email' has no 'Header' member
[E1101] maileater/models.py:527:8 : Module 'email' has no 'Encoders' member

However, all of these members are in fact in the email module:

$ ipython
Python 2.7.12 (default, Nov 19 2016, 06:48:10) 
Type "copyright", "credits" or "license" for more information.

IPython 4.0.0 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

In [1]: from email import MIMEBase, MIMEMultipart, MIMEText, Header, Encoders

In [2]: 
Do you really want to exit ([y]/n)? y

pylint --version output

pylint 1.7.4, 
astroid 1.5.3
Python 2.7.12 (default, Nov 19 2016, 06:48:10) 
[GCC 5.4.0 20160609]

All of this is happening in a virtualenv, and of course, that virtualenv is active for both the Pylint and the iPython run.

[selinium]

from email.MIMEMultipart import MIMEMultipart
Is the correct import for Python 2.x.

According to the Python 3 examples in the documentation, you need:

from email.mime.multipart import MIMEMultipart

[jrial]

The module seems to be doing some "weird" stuff, which might explain a bit.

In the __init__.py in the email library's root folder, we see the following:

_MIMENAMES = [
    # email.MIME<old name> -> email.mime.<new name is lowercased old name>
    'Audio',
    'Base',
    'Image',
    'Message',
    'Multipart',
    'NonMultipart',
    'Text',
    ]

# skipping some code

import email.mime
for _name in _MIMENAMES:
    importer = LazyImporter('mime.' + _name.lower())
    sys.modules['email.MIME' + _name] = importer
    setattr(sys.modules['email'], 'MIME' + _name, importer)
    setattr(sys.modules['email.mime'], _name, importer)

with the LazyImporter being defined as:

# Lazy loading to provide name mapping from new-style names (PEP 8 compatible
# email 4.0 module names), to old-style names (email 3.0 module names).
import sys

class LazyImporter(object):
    def __init__(self, module_name):
        self.__name__ = 'email.' + module_name

    def __getattr__(self, name):
        __import__(self.__name__)
        mod = sys.modules[self.__name__]
        self.__dict__.update(mod.__dict__)
        return getattr(mod, name)

@selinium your suggestion works on Python 2 as well. For now I'm going to solve it like that. Thanks for your input, which prompted me to dig a little deeper.

[PCManticore]

Given the weird stuff the email module is doing, I think it's safe to assume that we're not going to support this particular use case.