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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 start():
 action_set('meta.start', time.strftime('%Y-%m-%dT%H:%M:%SZ')) """ If the collectd charm is also installed, tell it to send a snapshot of the current profile data. """

        COLLECT_PROFILE_DATA = '/usr/local/bin/collect-profile-data'
        if os.path.exists(COLLECT_PROFILE_DATA):
            subprocess.check_output([COLLECT_PROFILE_DATA])