<p>I'm trying to insert some import lines into a python source file, but i would ideally like to place them right after the initial docstring. Let's say I load the file into the lines variable like this:</p>

<pre><code>lines = open('filename.py').readlines()
</code></pre>

<p>How to find the line number, where the docstring ends?</p>

If you're using the standard docstring format, you can do something like this:
```
```
count = 0
for line in lines:
    if line.startswith ('"""'):
        count += 1
        if count < 3:
            # Before or during end of the docstring
            continue
    # Line is after docstring
```
```
Might need some adaptation for files with no docstrings, but if your files are formatted consistently it should be easy enough.