擅长:python、mysql、java
<p>可以使用datetime.timedelta对象表示3周,然后将其添加到表示用户输入的datetime对象中。</p>
<pre><code>import datetime
date = raw_input("Enter date: ")
aDate = datetime.datetime.strptime(date,"%Y-%m-%d")
threeWeeks = datetime.timedelta(weeks = 3)
print aDate + threeWeeks
</code></pre>
<p>有关使用strtime方法的详细信息,请参见<a href="http://docs.python.org/library/datetime.html#strftime-and-strptime-behavior" rel="noreferrer">http://docs.python.org/library/datetime.html#strftime-and-strptime-behavior</a>。</p>