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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 generate_age(issue_time):
 """Generate a age parameter for MAC authentication draft 00."""

    td = datetime.datetime.now() - issue_time
    age = (td.microseconds + (td.seconds + td.days * 24 * 3600)
           * 10 ** 6) / 10 ** 6
    return unicode_type(age)