title: Insert characters in a string using python
body: <p>Here is what I am trying to achieve: I want to replace </p>
  
  <pre><code>void some_function(int,  int *, float);
  </code></pre>
  
  <p>with </p>
  
  <pre><code>void some_function(int a, int *b, float c);
  </code></pre>
  
  <p>So far, I have tried to replace "," with chr(97+i) as I loop through the string. </p>
  
  <pre><code>text = len("void some_function(int,  int *, float);")
  i = 0
  for j in range(0, length)
      if text[j] == ",":
         rep = " " + chr(97+i) + " .,"
         text = text.replace("," rep)
         i = i + 1
         j = 0 # resetting the index, but this time I want to find the next occurrence of "," which I am not sure
  </code></pre>
  
  <p>But this is not doing the job. Please let me know if there is a better way of doing this.</p>