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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 uptime():
 """Uptime of the host machine"""

    from datetime import timedelta

    with open('/proc/uptime', 'r') as f:
        uptime_seconds = float(f.readline().split()[0])
        uptime_string = str(timedelta(seconds=uptime_seconds))

    bob.says(uptime_string)