code: def util_dateFormat(self, field, formato=None):
          
          if not formato:
              try:
                  formato = self.__formatoFecha
              except AttributeError:
                  formato = "%Y-%m-%dT%H:%M:%S+0000"
          return datetime.strptime(datetime.strptime(field, "%Y-%m-%dT%H:%M:%S+0000").strftime(formato), formato)
docs: Converts a datetime field to a datetime using some specified format.
  
          What this really means is that, if specified format includes
          only for instance just year and month, day and further info gets
          ignored and the objects get a datetime with year and month, and
          day 1, hour 0, minute 0, etc.
  
          A useful format may be %Y%m%d, then the datetime objects
          effectively translates into date objects alone, with no relevant
          time information.
  
          PLEASE BE AWARE, that this may lose useful information for your
          datetimes from Mambu. Read this for why this may be a BAD idea:
          https://julien.danjou.info/blog/2015/python-and-timezones