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Python 2.7.9: No module named requests

I am writing a code in Python 2.7.9 for which I need the requests module. I installed the module using sudo pip install requests but still in python 2.7.9 I am getting an error as follows:
Python 2.7.9 (default, Jan 5 2016, 18:47:14)
[GCC 4.8.4] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import requests
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named requests
I checked the installation location /usr/local/lib/python2.7/dist-packages, it contains the requests package directory. The same thing works fine in python3, so I am guessing it's an installation error. How can I fix it ?
EDIT:
On executing pip lists, I could see requests (2.1.9) in the list. After I ran pip uninstall requests it shows requests (2.2.1) in pip list.

Based on the comments, it seems you have installed python 2.7.9 using a method Ubuntu doesn't like. Because of this the dist-packages folder is not added to your sys.path. You could set the PYTHONPATH variable in your .bashrc (or other zshrc, etc) to add that folder to your sys.path by default.
Better method would be to use a library like pyenv (It handles all dependency issues flawlessly for multiple python versions) or a better supported ppa for the latest python where this problem shouldn't arise at all.
Also, you have 2 versions of requests. This seems to be because one is installed using apt-get (sudo apt-get install python-requests) and the other is from pip (sudo pip install requests). It would be good to remove one of them to avoid confusion.

Why I can not use an installed module for python?

I have installed a python library MySQLdb, and it works yesterday. But today when I tried to run it, it goes on as following:
czhao#opx790:~$ python
Python 2.7.7 |Anaconda 2.0.1 (64-bit)| (default, Jun 2 2014, 12:34:02)
[GCC 4.1.2 20080704 (Red Hat 4.1.2-54)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
Anaconda is brought to you by Continuum Analytics.
Please check out: http://continuum.io/thanks and https://binstar.org
>>> import MySQLdb
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named MySQLdb
It is really strange, so I try to re-install it, but it seems I do have the library in my computer:
czhao#opx790:~$ sudo apt-get install python-mysqldb
[sudo] password for czhao:
Reading package lists... Done
Building dependency tree
Reading state information... Done
python-mysqldb is already the newest version.
The following packages were automatically installed and are no longer required:
libgooglepinyin0-dev linux-headers-3.2.0-27 linux-headers-3.2.0-41
linux-headers-3.2.0-37 linux-headers-3.2.0-43 linux-headers-3.2.0-61
patchutils linux-headers-3.2.0-37-generic linux-headers-3.2.0-27-generic
linux-headers-3.2.0-61-generic linux-headers-3.2.0-43-generic dpatch
linux-headers-3.2.0-41-generic
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 16 not upgraded.
I do not know why, I have the library but python keep tell me I do not have it.

You are using Anaconda Python, but the package installed with apt-get was installed for the system Python. These two different distributions have different library directories, so packages/modules installed with one are not available for the other.
To get around this, use the pip program that came with Anaconda and run sudo pip install MySQL-python.

Python3 pip installing globally when in a virtualenv

Attempting to finally make the jump to Python 3, but am running into some issues with virtualenvwrapper. I start out by creating the virtual environment like so:
mkvirtualenv -p /usr/local/bin/python3 projectname
which yields:
Running virtualenv with interpreter /usr/local/bin/python3
Using base prefix '/usr/local/Cellar/python3/3.3.3/Frameworks/Python.framework/Versions/3.3'
New python executable in projectname/bin/python3.3
Also creating executable in projectname/bin/python
Installing setuptools, pip...done.
So far, so good. I check the python console to make sure that the environment is looking at the correct interpreter and all that and it is. Here's where sadness happens (while the virtualenv is active):
pip install flask claims to be successful, but alas:
Python 3.3.3 (default, Jan 2 2014, 13:26:32)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import flask
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named 'flask'
Here's the issue:
$ pip show flask
---
Name: Flask
Version: 0.10.1
Location: /usr/local/lib/python3.3/site-packages
Requires: Werkzeug, Jinja2, itsdangerous
Unless I'm completely misunderstanding virtualenv/wrapper and their respective magics (which I very well could be), it seems like pip install is installing Flask globally rather than to the site-packages within my virtualenv, and thus the virtualenv is ignoring it.
Any clues what's going on here/how to fix? Am I wrong in assuming that virtualenvwrapper is ready for primetime with python3? Pretty solutions where I don't have to mangle my .bashrc or manually set environment variables are preferable. I'm hoping there's a way to do this through the api's provided by virtualenv and virtualenvwrapper.
Thanks!

I had problems with pip installing packages globally instead of in the activated virtualenv too. Have a look at pip installing in global site-packages instead of virtualenv for the question (and the answer).
Basically, the solution consisted of modifying the shebang of the pip scripts within the virtualenv as they pointed to the wrong python installation (global instead of in the virtualenv). Just change the shebang to point to the correct location and you're set.
Note: credit should go to Chase Ries who came up with the solution.

I had the same issue. It appears to be resolved as of Virtualenv 1.11.4.

WARNING: IPython History requires SQLite, your history will not be saved

Hi I'm using Ubuntu release 12.10 (quantal) 32-bit with Linux Kernel 3.5.0-21-generic. I'm trying to get IPython's History to work. I've set it up using pythonbrew and a virtual environment. In there I use pip to install IPython. Currently, when I start up IPython in a terminal I get:
WARNING: IPython History requires SQLite, your history will not be saved
Python 2.7.3 (default, Nov 8 2012, 18:25:10)
Type "copyright", "credits" or "license" for more information.
IPython 0.13.1 -- 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.
Searching on the warning in the first line, I found this issue report, so I went back and installed the following:
sudo apt-get install libsqlite0 libsqlite0-dev libsqlite3-0 libsqlite3-dev
and then removed and reinstalled pysqlite using pip
pip uninstall pysqlite
pip install pysqlite
After that I thought I would check the installation by importing the module:
Python 2.7.3 (default, Nov 8 2012, 18:25:10)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sqlite3
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/me/.pythonbrew/pythons/Python-2.7.3/lib/python2.7/sqlite3/__init__.py", line 24, in <module>
from dbapi2 import *
File "/home/me/.pythonbrew/pythons/Python-2.7.3/lib/python2.7/sqlite3/dbapi2.py", line 27, in <module>
from _sqlite3 import *
ImportError: No module named _sqlite3
So now it seems the file _sqlite3.so can't be found. That's when I found this SO question. Either it doesn't exist or it's not in my PYTHONPATH environment variable. Searching for the file, I get:
$ locate _sqlite3.so
/home/me/Desktop/.dropbox-dist/_sqlite3.so
/home/me/epd/lib/python2.7/lib-dynload/_sqlite3.so
/usr/lib/python2.7/lib-dynload/_sqlite3.so
So the file is there, but when I looked in my python path:
import sys
for p in sys.path:
print p
none of the above paths that contain _sqlite3.so were contained in my PYTHONPATH. For giggles, I added the path /usr/lib/python2.7/lib-dynload to my PYTHONPATH in a terminal and then tried to import sqlite3 again:
Python 2.7.3 (default, Nov 8 2012, 18:25:10)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.path.append("/usr/lib/python2.7/lib-dynload")
>>> import sqlite3
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/me/.pythonbrew/pythons/Python-2.7.3/lib/python2.7/sqlite3/__init__.py", line 24, in <module>
from dbapi2 import *
File "/home/me/.pythonbrew/pythons/Python-2.7.3/lib/python2.7/sqlite3/dbapi2.py", line 27, in <module>
from _sqlite3 import *
ImportError: /usr/lib/python2.7/lib-dynload/_sqlite3.so: undefined symbol: PyUnicodeUCS4_DecodeUTF8
Uh oh. Now I'm completely stuck. Can anyone help me out? I've also read in a few places that I may have to rebuild Python. I have no idea how to do this in pythonbrew. Can anyone point me in the right direction?

I've also read in a few places that I may have to rebuild Python.
This is correct. SQLite is part of the standard library,
and is built when you compile Python. There are a few 'optional' parts
of the standard library, which Python will simply skip (with minimal warning, unfortunately)
if the dependencies are missing at build time, and sqlite is one of these.
You should be able to just install libsqlite3-dev,
then rebuild Python and you should be set.
Keep an eye on the build messages,
as they do report which modules they are skipping due to missing dependencies.

Thanks to minrk for pointing me in the right direction. All I had to do was rebuild python. I've outlined the steps below for those that are using pythonbrew. Notice that I already installed the libsqlite3-dev package up in the question section.
First, with the proper version of python and virtual environment loaded up run the command:
$ pip freeze -l > requirements.txt
This gives us a text file list of all of the pip packages that have been installed in the virtual environment for this particular python release in pythonbrew. Then we remove the version of python from pythonbrew and reinstall it (this is the "rebuild python" step):
$ pythonbrew uninstall 2.7.3
$ pythonbrew install 2.7.3
After that, we switch over to the newly installed python version 2.7.3 and create a new virtual environment (which I've called "sci"):
$ pythonbrew switch 2.7.3
$ pythonbrew venv create sci
$ pythonbrew venv use sci
Ideally you should be able to run the command:
$ pip install -r requirements.txt
and according to this pip should reinstall all the modules that you had in the virtual environment before we clobbered that version of python (2.7.3). It didn't work for me for whatever reason so I manually installed all of the modules using pip individuality.
$ ipython --pylab
Python 2.7.3 (default, Jan 5 2013, 18:48:27)
Type "copyright", "credits" or "license" for more information.
IPython 0.13.1 -- 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.
and IPython history works!

What worked for me (using osx + homebrew + brewed python):
# Reinstall Python 2.7 with sqlite
brew remove python
brew install readline sqlite gdbm --universal
brew install python --universal --framework
# Reinstall iPython with correct bindings
pip uninstall ipython
pip install ipython
And you should be good to go.

You should rebuild your python with sqlite support
sudo apt-get install libsqlite3-dev
wget https://www.python.org/ftp/python/2.7.15/Python-2.7.15.tgz
tar -xvf Python-2.7.15.tgz
cd Python-2.7.15
./configure
make
sudo make install
Recreate your virtual environment and you should be good to go
rmvirtualenv venv
mkvirtualenv -p python2 venv
workon venv
pip install -r requirements.txt
# or
pip install ipython

This warning appears on macOS when python is installed with pyenv. By default it installs python without sqlite. These commands reinstall python with sqlite support:
pyenv uninstall 3.7
CFLAGS="-I$(xcrun --show-sdk-path)/usr/include" pyenv install 3.7

python mysqldb import error

on ubuntu i have installed mysql but still i cannot import mysql database. Below are the steps that i followed.Can any one point me to a solution to this
(Other info is ubuntu is installed on a virtual box hope that should not matter).Python version is 2.6.5
root#rajeev-laptop:/opt/s/site# apt-get install python-mysqldb
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
linux-headers-2.6.32-21 linux-headers-2.6.32-21-generic
Use 'apt-get autoremove' to remove them.
Suggested packages:
python-mysqldb-dbg
The following NEW packages will be installed:
python-mysqldb
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B/76.6kB of archives.
After this operation, 283kB of additional disk space will be used.
Selecting previously deselected package python-mysqldb.
(Reading database ... 151280 files and directories currently installed.)
Unpacking python-mysqldb (from .../python-mysqldb_1.2.2-10build1_i386.deb) ...
Setting up python-mysqldb (1.2.2-10build1) ...
Processing triggers for python-support ...
root#rajeev-laptop:/opt/s/site# python
Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import MySQLdb
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named MySQLdb
>>>

All,
I got this resolved by the following, in my /etc/bash.bashrc i was importing a pythonpath as /opt/s/
Where django and my site resided.When i removed the following from the pythonpath the import MySQLdb worked..Hope this post will help somebody..

Ahh these problem... invest some time in virtualenv for python. It will pay off =)

I would check the Python PATH and make a manual build of MySQLDB download. Download the installation files from this source forge site.

The package information shows you what's going on (ubuntu 12.04):
apt-cache show python-mysqldb
[...]
Provides: python2.7-mysqldb
Depends: python2.7, [...]
Python-Version: 2.7
[...]
This package is for python 2.7 - so it's not installed for 2.6. execute python2.7 in a shell and try the import again.
(if you have an older ubuntu version, execute the apt-cache command on your machine to check if this is the case in your version as well)