title: Python code doesn't execute. No errors showed
body: <p>I don't know what's wrong with my code. It would just not execute. Nothing happens, no errors occur. I can't figure it out. 
  If someone can tell me what I have done wrong, please do so and I will be grateful.</p>
  
  <pre><code>class Money (object):
      def __init__ (self, euro, cent):
        self.euro = euro
        self.cent = cent
  
      def __str__ (self):
          if self.cent &gt;= 100:
              r = self.cent / 100
              self.cent = self.cent % 100
              self.euro = self.euro + r
              return ("%d EUR &amp; %d cents") % (self.euro, self.cent)
          else:
              return ("%d EUR &amp; %d cents") % (self.euro, self.cent)
  
      def changeCent (self):
          #100 c = 1 E
          cents = self.euro * 100
          self.cent = self.cent + cents
          return self.cent
  
      def changeSum (self, euros):
          #1 E = 100 c
          euros = self.cent / 100
          self.euro = self.euro + euros
          return self.euro
  
      def debt (self, years, rate):
          value = Money()
          multiply = rate * years * 12 / 100
          value.euro = self.euro * multiply
          value.cent = self.cent * multiply
          if value.cent &gt; 100:
              euro_ = value.cent / 100
              value.cent = value.cent - 100
              value.euro = value.euro + euro_
          return value
  
  def main():
      x = Money()
      x.euro = int(input("Type in your EURO ammount: \n"))
      x.cent = int(input("Type in your CENT ammount: \n"))
      print (x)
  </code></pre>