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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 last(conf):
 """How long you have kept signing in."""

    try:
        v2ex = V2ex(conf.config)
        v2ex.login()
        last_date = v2ex.get_last()
        click.echo(last_date)
    except KeyError:
        click.echo('Keyerror, please check your config file.')
    except IndexError:
        click.echo('Please check your username and password.')