pyqgis - QGIS start-up error message: "Couldn't load plugin MetaSearch due to an error when calling its classFactory() method"

I'm an Ubuntu 16.04 (64-bit) user and I just recently upgraded my QGIS instalation (from 2.14, "Essen", to 2.16, "Nødebo").

I'm not a programmer and I know little about the details of how python works, much less about how QGIS and python relate, so when I get this message at start-up, I don't really know what to do about it:

Couldn't load plugin MetaSearch due to an error when calling its classFactory() method 


ImportError: No module named requests 
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/qgis/utils.py", line 333, in startPlugin
    plugins[packageName] = package.classFactory(iface)
  File "/home/jmb/.qgis2/python/plugins/MetaSearch/__init__.py", line 29, in classFactory
    from MetaSearch.plugin import MetaSearchPlugin
  File "/usr/lib/python2.7/dist-packages/qgis/utils.py", line 607, in _import
    mod = _builtin_import(name, globals, locals, fromlist, level)
  File "/home/jmb/.qgis2/python/plugins/MetaSearch/plugin.py", line 31, in 

    from MetaSearch.dialogs.maindialog import MetaSearchDialog
  File "/usr/lib/python2.7/dist-packages/qgis/utils.py", line 607, in _import
    mod = _builtin_import(name, globals, locals, fromlist, level)
  File "/home/jmb/.qgis2/python/plugins/MetaSearch/dialogs/maindialog.py", line 44, in 
    from owslib.csw import CatalogueServiceWeb
  File "/usr/lib/python2.7/dist-packages/qgis/utils.py", line 607, in _import
    mod = _builtin_import(name, globals, locals, fromlist, level)
  File "/usr/share/qgis/python/owslib/csw.py", line 27, in 
    from owslib.util import OrderedDict
  File "/usr/lib/python2.7/dist-packages/qgis/utils.py", line 607, in _import

    mod = _builtin_import(name, globals, locals, fromlist, level)
  File "/usr/share/qgis/python/owslib/util.py", line 35, in 
    import requests
  File "/usr/lib/python2.7/dist-packages/qgis/utils.py", line 607, in _import
    mod = _builtin_import(name, globals, locals, fromlist, level)
ImportError: No module named requests


Python version: 2.7.11+ (default, Apr 17 2016, 14:00:29) [GCC 5.3.1 20160413] 
QGIS version: 2.16.1-Nødebo Nødebo, 8545b3b 


Python Path:
/usr/share/qgis/python
/home/jmb/.qgis2/python
/home/jmb/.qgis2/python/plugins
/usr/share/qgis/python/plugins
/usr/lib/python2.7
/usr/lib/python2.7/plat-x86_64-linux-gnu
/usr/lib/python2.7/lib-tk
/usr/lib/python2.7/lib-old

/usr/lib/python2.7/lib-dynload
/usr/local/lib/python2.7/dist-packages
/usr/lib/python2.7/dist-packages
/usr/lib/python2.7/dist-packages/PILcompat
/usr/lib/python2.7/dist-packages/gtk-2.0
/home/jmb/.qgis2//python

Note that I can ignore this message and work in QGIS without further issues.

Anyways, can anyone tell me how to fix this?

---

In case it matters, here are the commands used for upgrading QGIS:

sudo apt-get update
sudo apt install qgis python-qgis qgis-plugin-grass

And these are the lines in my relevant lines from the /etc/apt/sources.list file:

deb http://qgis.org/debian xenial main
deb-src http://qgis.org/debian xenial main

---

Note2: can this be originated by the non ASCII character in the QGIS version "Nødebo"?

Answer

Had the same error, found the solution here: QGIS issues

Just run:

sudo pip install requests

to install the required module.