HOW-TO Set timestamps from the awe-prompt

Time stamps and validity of a frame are usually set by the Calibration Time-stamp editor web service CalTS, but they can also be changed at the awe-prompt. Updating attributes via the awe-prompt is done with the context interface. For each updatable attribute there is a corresponding method on the context object.Notice that only the timestamp_start, timestamp_end and is_valid (super flag) can be updated.

Python example:

     # query for a BiasFrame
awe> qry = == 'WFI'
awe> bias = qry[0]
     # substract one day from the timestamps start
awe> context.update_timestamp_start(bias, bias.timestamp_start - datetime.timedelta(1))
     # and set timestamp_end to a specific date
awe> context.update_timestamp_start(bias, datetime.datetime(2010, 1, 1))
     # make the BiasFrame invalid
awe> context.update_is_valid(bias, 0)
     # make the BiasFrame valid again
awe> context.update_is_valid(bias, 1)