Use a Library Locally Instead of Installing It

Use a library locally instead of installing it

EDIT: This answer is outdated. You should be using VirtualEnv. If you are allergic to third-party software for some reason (in which case, why are you installing libraries?), there is something called venv, that is literally built into python3, so there is no excuse not to use some kind of virtualization. (Most people active in the community prefer VirtualEnv, however. See https://stackoverflow.com/a/41573588/410889.)

VirtualEnv installs a local python interpreter, with a local packages folder and everything. In addition to this entirely solving the issue of administrative privileges, the most important feature of VirtualEnv is that it allows you to keep your environments separate. If you have one project that needs Foo version 2.3 and another that needs Foo version 1.5, you can't have them share the same environment; you have to keep their environments separate with VirtualEnv.

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There are a few possibilities:

If you already know how to install Python modules, the default distutils setup already includes a per-user installation option. Just run python setup.py install --user instead of python setup.py install. This is the easiest, since this does not necessitate the addition of any source code.

You could also run the script with the directory of tweepy as the current working directory.

You could add an environment variable named PYTHONPATH to whatever environment (e.g., the shell) you use to run your script, and make it contain the path to tweepy.

If all else fails, and you really do want to edit your source code, you'll need to edit sys.path. sys.path is a list of locations where Python will look for code.

In your code, write:

import sys
sys.path.append("/path/to/your/tweepy/directory")

import tweepy

How to use local python library

If you are working in a virtualenv, you can just try:

pip install -e <path to the lib>

The -e flag makes the install editable, this means that if you do changes on the steampy repo, those will be available on the virtualenv.

Unable to import a module that is definitely installed

In my case, it is permission problem. The package was somehow installed with root rw permission only, other user just cannot rw to it!

How to import standard library module instead of local directory?

The problem is that the current working directory (as either '' or '.', depending on version/platform) is always at the top of sys.path when you start up Python.

Using absolute imports makes no difference—that just means to look in sys.path first, instead of looking for relative imports before falling back to sys.path.

The right solution is obviously to either (a) rename calendar, or (b) move it into subpackage of some other package instead of having it at the top level. Whatever your Good Reasons are, the Good Reasons for doing the right thing are likely even better.

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But if you must get around this, there are a few things you can do. The simplest is to temporarily munge sys.path:

syspath = sys.path
sys.path = [path for path in sys.path if path.strip('.')]
import calendar
sys.path = syspath

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However, no matter what you do, this is going to cause huge problems. When you later try to import your local package calendar—even if you're doing so from a completely different source file—nothing will happen, because there's already something named calendar in sys.modules, so that other source file will just get the stdlib calendar module instead of your package.

So you'll also need to rename one or the other on the fly and remove it from sys.modules. Maybe this:

syspath = sys.path
sys.path = [path for path in sys.path if path.strip('.')]
calmod = sys.modules.get('calendar')
del sys.modules['calendar']
calendar = __import__('calendar')
sys.modules['calendar'] = calmod
sys.path = syspath

And, depending on the order at which your modules get run (which may not be easily predictable, or even deterministic), there's a good chance you'll need similar hackery in the other location.

(What if you never actually need to import your local package calendar? Well, in that case you don't have this problem… but then I can't imagine what your Good Reasons could possibly be…)

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