Using spaces

class PreformatedTest:
    """ Testing preformatted text """
    print "Using spaces"

Using tabs

class PreformatedTest:
	""" Testing preformatted text """
	print "Using tabs"

Mixsing tabs and spaces (bad)

class PreformatedTest:
    """ Testing preformatted text """
    print "Using spaces"
	print "And tabs (blah)"