def posix_to_dt_str(posix):
 dt = datetime.datetime.utcfromtimestamp(posix)
 dt_str = dt.strftime(_DT_FORMAT)
 return (dt_str + '.000Z')

def posix_to_dt_str ( posix ) : dt = datetime . datetime . utcfromtimestamp ( posix ) dt_str = dt . strftime ( _DT_FORMAT ) return ( dt_str + '.000Z' )
reverse of str_to_datetime .