title: "Try and Except" to differentiate between strings and integers?
body: <p>I'm a beginner in the Python language. Is there a "try and except" function in python to check if the input is a LETTER or multiple LETTERS. If it isn't, ask for an input again? (I made one in which you have to enter an integer number)</p>
  
  <pre><code>def validation(i):
  try:
      result = int(i)
      return(result)
  except ValueError:
      print("Please enter a number")
  
  def start():
  x = input("Enter Number: ")
  z = validation(x)
  if z != None:
  
      #Rest of function code
      print("Success")
  else:
      start()
  start()
  </code></pre>
  
  <p>When the above code is executed, and an integer number is entered, you get this:</p>
  
  <pre><code>Enter Number: 1
   Success
  </code></pre>
  
  <p>If and invalid value however, such as a letter or floating point number is entered, you get this:</p>
  
  <pre><code>Enter Number: Hello
  Please enter a number
  Enter Number: 4.6
  Please enter a number
  Enter Number: 
  </code></pre>
  
  <p>As you can see it will keep looping until a valid <strong>NUMBER</strong> value is entered. So is it possible to use the "try and except" function to keep looping until a  <strong>letter</strong>  is entered? To make it clearer, I'll explain in vague structured English, not pseudo code, but just to help make it clearer:</p>
  
  <pre><code>print ("Hello this will calculate your lucky number")
  
  # Note this isn't the whole program, its just the validation section.
   input (lucky number)
  # English on what I want the code to do: 
  
      x = input (luckynumber)
  </code></pre>
  
  <p>So what I want is that if the variable "x" IS NOT a letter, or multiple letters, it should repeat this input (x) until the user enters a valid <strong>letter</strong> or multiple <strong>letters</strong>. In other words, if a letter(s) isn't entered, the program will not continue until the input is a letter(s). I hope this makes it clearer.</p>