title: Function in a python class that is not a method
body: <p>I have a class that needs auxiliary functions, e.g. one to calculate a checksum that just uses the passed in arguments and not any properties of the class. This function is only called by the class's methods. So I dont need to pass in the 'self' as the first formal of the function.</p>
  
  <p>How should I implement these functions? Can I have non-method functions in a class? Should I define them outside the class (even though they are not used by anything else)? Or is it ok for them to be regular methods?</p>