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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def stop(ctx, description, f):
 """ Use it when you stop working on the current task. You can add a description to what you've done. """

    description = ' '.join(description)
    try:
        timesheet_collection = get_timesheet_collection_for_context(ctx, f)
        current_timesheet = timesheet_collection.latest()
        current_timesheet.continue_entry(
            datetime.date.today(),
            datetime.datetime.now().time(),
            description
        )
    except ParseError as e:
        ctx.obj['view'].err(e)
    except NoActivityInProgressError as e:
        ctx.obj['view'].err(e)
    except StopInThePastError as e:
        ctx.obj['view'].err(e)
    else:
        current_timesheet.save()