title: Using NumPy to Find Median of Second Element of List of Tuples
body: <p>Let's say I have a list of tuples, as follows:</p>
  
  <pre><code>list = [(a,1), (b,3), (c,5)]
  </code></pre>
  
  <p>My goal is to obtain the first element of the median of the list of tuples, using the tuples' second element. In the above case, I would want an output of b, as the median is 3. I tried using NumPy with the following code, to no avail:</p>
  
  <pre><code>import numpy as np
  
  list = [('a',1), ('b',3), ('c',5)]
  np.median(list, key=lambda x:x[1])
  </code></pre>