code: def datetime_from_iso_format(string):
      
      match = DATE_ISO_REGEX.match(string)
      if match:
          date = datetime.datetime(year=int(match.group(DATE_ISO_YEAR_GRP)),
                                   month=int(match.group(DATE_ISO_MONTH_GRP)),
                                   day=int(match.group(DATE_ISO_DAY_GRP)),
                                   hour=int(match.group(DATE_ISO_HOUR_GRP)),
                                   second=int(match.group(DATE_ISO_SEC_GRP)),
                                   minute=int(match.group(DATE_ISO_MIN_GRP)))
          return date
      else:
          return None
docs: Return a datetime object from an iso 8601 representation.
      Return None if string is non conforming.