def iso8601_date(s):
try:<EOL><INDENT>return datetime.datetime.strptime(s, ISO8601_DATE_FORMAT).replace(tzinfo=pytz.utc).date()<EOL><DEDENT>except (TypeError, ValueError):<EOL><INDENT>return s<EOL><DEDENT>
Parses an ISO 8601 date string and returns a UTC date object or the string
if the parsing failed.
:param s: ISO 8601-formatted date string (2015-01-25)
:return: