title: Extract data from fields which contains multiple values
body: <p>I am new to python programming and data mining. I am trying to read data from .csv file and store them as the list of dictionaries for analysis. But my data has multiple alternatives for a single column of values.
  Here is my Data sample</p>
  
  <p><a href="https://i.stack.imgur.com/v37zk.jpg" rel="nofollow noreferrer">The screenshot of my data along with Highlighter</a></p>
  
  <p>Since my column Fuels has Gas/Electricity I have City MPG as 16/81. However when I read this into my list of dictionaries, it isn't much of a problem, but if I want to compute an average or sum it gives an error.</p>
  
  <p>I want to have such columns separated when I read the data into Python.</p>
  
  <pre><code>import csv
  
  with open('mpg.csv') as f:
   a = [{k: (v) for k, v in row.items()}
    for row in csv.DictReader(f, skipinitialspace=True)]
  print(a, '\n')
  print(len(a))  # simply printing the data
  print(a[0].keys()) # printing the Headers of the data
  z = sum(float(d['City MPG']) for d in a) / len(a) # Error code
  print(z)
  </code></pre>
  
  <p>The error is <code>ValueError: could not convert string to float: '33/81</code>.
  I understand the error. </p>
  
  <p>I am thinking of inserting such values in a Map, but not sure about the code.</p>