How to open files in Python

>>> import os
>>> os.chdir('/mlab/data/billcx/Desktop')
>>> os.getcwd()
'/mlab/data/billcx/Desktop'
>>> import glob
>>> glob.glob('*')
['eclipse.desktop', 'google-chrome.desktop', 'Chem_695_Title_Page_F2012.pdf', 'Lit_Seminar_Eval_criteria_F2012.pdf', 'SEPH_Overview_v6.2.pdf', 'firefox.desktop', 'canopy.desktop', '1.html', 'Untitled 1.csv']