title: Replacing characters of string in a list
body: <p>I am replacing the character and/or string in l3 by comparing it with l1 and l2 . What output I am getting and what output I like to get is shown below.</p>
  
  <p>my code </p>
  
  <pre><code>l1 = ["Jai","Sharath","Ravi","Aditya"]
  l2 = ["Singh","Kumar","Sharma","Rao"]
  l3 = ["J.Singh","Sharath_K","R-Sharma","Rao_Aditya"]
  for x,y,z in zip(l1,l2,l3):
    if x in z:
      z.replace(x,"Firstname")
    elif x[0] in z:
      z.replace(x[0],"First/Character/of/first/name")
    elif y in z:
      z.replace(y,"lastname")
    else:
      z.replace(y[0],"First/Character/of/last/name")
  </code></pre>
  
  <p>my output</p>
  
  <pre><code>'First/Character/of/first/name.Singh'
  'Firstname_K'
  'First/Character/of/first/name/Sharma'
  'Rao_Firstname'
  </code></pre>
  
  <p>my expected output</p>
  
  <pre><code>'First/Character/of/first/name.lastname'
  'Firstname_First/Character/of/last/name'
  'First/Character/of/first/name/lastname'
  'lastname_Firstname'
  </code></pre>
  
  <p>how do i get my desired output?</p>