擅长:python、mysql、java
<p>从<a href="https://docs.python.org/2/tutorial/inputoutput.html" rel="nofollow">python doc</a>:</p>
<blockquote>
<p>if f.readline() returns an empty string, the end of the file has been reached, while a blank line is represented by '\n', a string containing only a single newline.</p>
</blockquote>