[Solved] Class in Python [closed]

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class Bird(object):
    def __init__(self, height, weight, has_feathers, capable_of_flying, bird_migrates, bird_sings, bird_eats_worms):
        self.height = height
        self.weight = weight
        self.has_feathers = has_feathers
        self.capable_of_flying = capable_of_flying
        self.bird_migrates = bird_migrates
        self.bird_sings = bird_sings
        self.bird_eats_worms = bird_eats_worms

    def get_height(self):
        return self.height

    def get_weight(self):
        return self.weight

    def get_has_feathers(self):
        if self.has_feathers:
            return "The bird has feathers"
        else:
            return "The bird does not have feathers"

    # Etc...

A few things of note:

  • You cannot have a function and variable of the same name, so I had to rename the functions to “get_…”
  • If you want to make a function part of a class (called a method) then it has to be indented to be in the class.
  • A class method needs to have the class object passed to it as the first parameter (called self by convention). This is how the class knows information about itself.
  • The variables in the class need to be accessed with classvar.variable, where inside the class classvar is self.
  • CamelCase should only be used for class names in python. Use all_lower_case_and_underscore for variable and function names.

You would use the class like this:

penguin = Bird(10, 30, True, False, False, True, False)
print penguin.get_has_feathers() # "The bird has feathers"

The whole “get_…” paradigm is an “anti-pattern” in python (you might have a C++ background where this is considered the correct way to do it). It’s better to just expose the variables directly:

class Bird(object):
    def __init__(self, height, weight, has_feathers, capable_of_flying, bird_migrates, bird_sings, bird_eats_worms):
        self.height = height
        self.weight = weight
        if has_feathers:
            self.has_feathers = "The bird has feathers"
        else:
            self.has_feathers = "The bird does not have feathers"
        # etc...

penguin = Bird(10, 30, True, False, False, True, False)
print penguin.has_feathers # "The bird has feathers"

solved Class in Python [closed]