title: TypeError: '>=' not supported between instances of 'NoneType' and 'float'
body: <p>Not sure what I am doing wrong here. The error seems to be coming from <code>def get_win_percentage</code>:</p>
  <pre><code>class Team:
      def __init__(self):
          self.team_name = 'none'
          self.team_wins = 0
          self.team_losses = 0
  
      def get_win_percentage(percent):
          percent = float(team_wins) / float(team_wins + team_losses)
          
  if __name__ == &quot;__main__&quot;:
      team = Team()
     
      team_name = input()
      team_wins = int(input())
      team_losses = int(input())
      
      team.team_name = team_name
      team.team_wins = team_wins
      team.team_losses = team_losses
      
      if team.get_win_percentage() &gt;= 0.5:
          print('Congratulations, Team', team.team_name,'has a winning average!')
      else:
          print('Team', team.team_name, 'has a losing average.')
  </code></pre>
  <p>error message:</p>
  <pre><code>Traceback (most recent call last):
    File &quot;main.py&quot;, line 24, in &lt;module&gt;
      if team.get_win_percentage() &gt;= 0.5:
  TypeError: '&gt;=' not supported between instances of 'NoneType' and 'float'
  </code></pre>