@classmethod<EOL><INDENT>def tuple_to_str(cls, t):<DEDENT>
return '<STR_LIT:/>'.join(six.text_type(part) for part in t if part is not None)<EOL>
Converts a (project, activity) tuple to a string in the format xxx/yyy, or a (project, activity, role) tuple in
the format xxx/yyy/zzz.