$ cat triple.py
    def foo():
        print """this is a triple quoted string
                 this is a continuation of a triple quoted string"""

    if __name__ == '__main__':
        foo()
    $ python triple.py
    this is a triple quoted string
                     this is a continuation of a triple quoted string

This is really warty. In bash you can mostly get around this with <<- for here documents (which removes leading indentation, so even if you're defining a here doc at a place that itself is indented, you don't have to align the text to the left column yourself). The man page in my version suggests it only works for leading tabs, not spaces, though.

e.g.

    $ function usage() {
            cat <<-END
                    this is a here document that
                    spans multiple lines and is indented
            END
    }
    $ usage
    this is a here document that
    spans multiple lines and is indented
    $