'Test for when a non-existing course key is entered'

def test_course_key_not_found(self):

    errstring = "Course    with    'TestX/TS01/2015_Q7'    key    not    found."
    with self.assertRaisesRegexp(CommandError, errstring):
        call_command('delete_course', 'TestX/TS01/2015_Q7')
