How do I split a string at only some commas, not all? : <p>I'm pretty inexperienced at programming, and I've been doing a lot of practice problems recently. I'm currently attempting to find the sum of the x and y values of the two closest points in <a href="https://d18l82el6cdm1i.cloudfront.net/uploads/documents/points-oWGbRs2l1v.txt" rel="nofollow noreferrer">this</a>
set of points. The problem I'm having, is because there are commas separating the points but also in the points, I don't know how to split the string to make a list of the points</p>

<p>This is my code right now:</p>

<pre><code>import csv

with open('points.csv') as f:
    reader = csv.reader(f)
    header_row = next(reader)
    print(header_row)
</code></pre>

<p>and the output is:</p>

<pre><code>['{{253', ' 146}', ' {3', ' 845}', ' {-841', ' 337}', -SNIP- ' {-918', ' -736}', ' {269', ' 212}', ' {126', ' 146}}']
</code></pre>

<p>How do I change this code so it splits at only some commas, not all of them?</p>
