title: Python Restaurant Tip Calculator
body: <p>So I am a complete newbie to coding and need some help. I am trying to create a code for a tip calculator but am not quite sure where I am going with it. I was never in class to be taught by my teacher so I am going out on a whim with this. There is a requirement to have a class but <em>I know</em> I am going about it the wrong way. Any help is appreciated.
  This is what I have so far:</p>
  
  <pre><code>import decimal
  
  class Tip:
  
      def __init__(self):
          self.tip=0
  
      def __str__(self):
          return 'Tip['+str(self.sub_total)+' * '+str(self.percentage)+']'
  
      def sub_total():
          self.sub_total = input()
  
      def percentage():
          self.percentage = input()
  
      def get_tip(percentage, sub_total):
          self.percentage = decimal.Decimal(percentage)
          self.sub_total = decimal.Decimal(sub_total)
          self.tip = ((sub_total * percentage) / 100)
          self.total = (sub_total + tip)
          return self.__str__()
  
  t = Tip()
  
  print ("How much is the bill?")
  t.sub_total()
  
  print ("What percentage should the tip be?")
  t.percentage()
  
  print (t.get_tip())
  </code></pre>
  
  <p>Everytime I run it I get this:</p>
  
  <pre><code>get_tip() takes exactly 2 arguments (1 given)
  </code></pre>
  
  <p>Like I said, I am kindof making it up as I go and any help is appreciated. </p>