add text in a file with python (without replacing it)
<p>I have a file with ids and information, like this:</p>

<pre><code>1oMZgkoaz3o 2011-12-29T01:23:00.000Z 9 503 ApolloIsMyCoPilot
nUW1TomCSQg 2011-12-29T01:23:15.000Z 9 348 grea7stuff
tJuLnRrAcs0 2011-12-29T01:26:20.000Z 9 123 AdelGaming
tyi5g0mnPIs 2011-12-29T01:28:07.000Z 9 703 PreferredGaming
</code></pre>

<p>and I want to add a flag on some of the line, so if I have a dictionary</p>

<pre><code>flags = {'1oMZgkoaz3o': flag1, 'tJuLnRrAcs0': flag2}
</code></pre>

<p>the result I want is </p>

<pre><code>1oMZgkoaz3o 2011-12-29T01:23:00.000Z 9 503 ApolloIsMyCoPilot flag1
nUW1TomCSQg 2011-12-29T01:23:15.000Z 9 348 grea7stuff
tJuLnRrAcs0 2011-12-29T01:26:20.000Z 9 123 AdelGaming flag2
tyi5g0mnPIs 2011-12-29T01:28:07.000Z 9 703 PreferredGaming
</code></pre>

<p>So I made this code</p>

<pre><code>l = True
while l is True:
    a = f.readline()
    try a.split(' ')[0] in flags.iterkeys():
        f.seek(-1,1)
        f.write(' '+str(flags[a.split(' ')[0]])+'\n')
        del flags[a.split(' ')[0]]
    except IndexError:
        l = False
</code></pre>

<p>so, my Python code could be poor, but the problem is that with this code I'm replacing text, so the file is all messed up. How can I write without replacing? and if you have better ideas for the code, you are welcome...</p>
