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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 grok_seconds(lease):
 """Ensures that we are returning just seconds"""

    if lease.endswith('s'):
        return int(lease[0:-1])
    elif lease.endswith('m'):
        return int(lease[0:-1]) * 60
    elif lease.endswith('h'):
        return int(lease[0:-1]) * 3600

    return None