在Python 3中使用导入保管箱时出现语法错误

Question

I'm trying to use Dropbox with Python 3. It appears to install OK but when I try to import it, I get a syntax error (see below). It's only supported on 3.4+ and I'm using 3.2... I wondered if that's the problem but I found a website (in the original German or in English using Google Translate which doesn't get the formatting quite right) which is using Dropbox with Python 3.2 on a Raspberry Pi - and that's exactly what I want to do.

Thanks in advance - any help or suggestions would be appreciated.

pi@jsmd ~ $ sudo pip-3.2 install --upgrade dropbox
Requirement already up-to-date: dropbox in /usr/local/lib/python3.2/dist-packages/dropbox-4.0-py3.2.egg
Requirement already up-to-date: urllib3 in /usr/local/lib/python3.2/dist-packages (from dropbox)
Requirement already up-to-date: requests>=2.5.1 in /usr/local/lib/python3.2/dist-packages (from dropbox)
Requirement already up-to-date: six>=1.3.0 in /usr/local/lib/python3.2/dist-packages (from dropbox)
Cleaning up...

pi@jsmd ~ $ python3.2
Python 3.2.3 (default, Mar  1 2013, 11:53:50)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.

>>> import dropbox
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.2/dist-packages/dropbox-4.0-py3.2.egg/dropbox/__init__.py", line 3, in <module>
    from .dropbox import __version__
  File "/usr/local/lib/python3.2/dist-packages/dropbox-4.0-py3.2.egg/dropbox/dropbox.py", line 19, in <module>
    from .base import DropboxBase
  File "/usr/local/lib/python3.2/dist-packages/dropbox-4.0-py3.2.egg/dropbox/base.py", line 7, in <module>
    from . import (
  File "/usr/local/lib/python3.2/dist-packages/dropbox-4.0-py3.2.egg/dropbox/files.py", line 5157
    Metadata._parent_shared_folder_id_validator = bv.Nullable(bv.String(pattern=u'[-_0-9a-zA-Z:]+'))
                                                                                                 ^
SyntaxError: invalid syntax

Answer 1

The current version of the provided Dropbox Python SDK uses the u'...' notation to define Unicode literals. This is a syntax introduced in Python 3.3 to assist in writing code that works both on Python 2 and 3.

The blog post doesn't detail how they managed to skirt the minimum requirements; I can only think that the library has been updated to take advantage of newer Python features to simplify polyglot Python code after the post was published .

The current dropbox package version is 4.0; take a look through the versions on the simple pypi page for the package and see if an earlier version works for you, instead.

I'm not sure the version the blog used is available though. Version 3.12 was published to PyPI in August 2015, so well after May 2015 (when the blog post was posted) and already requires Python 3.3 or newer (judging by the initial API v2 commit on Github ). The next older release is version 2.2.0 , which goes back to September 2014 and uses Dropbox API version 1.