Using composition

composition.py

from abc import ABCMeta, abstractmethod


class Renderer(metaclass=ABCMeta):
    def __init__(self, entity):
        self._entity = entity
    
    @abstractmethod
    def __call__(self):
        raise NotImplementedError


class IntRenderer(Renderer):
    type_ = int
    
    def __call__(self):
        assert isinstance(self._entity, self.type_)
        
        return 'INTEGER {}'.format(self._entity)


class FloatRenderer(Renderer):
    type_ = float
    
    def __call__(self):
        assert isinstance(self._entity, self.type_)
        
        return 'FLOAT {}'.format(self._entity)


class CompositeRenderer(Renderer):
    _classes = [
        IntRenderer,
        FloatRenderer,
    ]
    
    def __call__(self):
        for render_class in self._classes:
            if isinstance(self._entity, render_class.type_):
                renderer = render_class(self._entity)
                return renderer()
        
        raise TypeError('Not recognized')


if __name__ == '__main__':
    numbers = [10, 4.1, 91.1, 1000]
    for number in numbers:
        renderer = CompositeRenderer(number)
        print(renderer())

    '''
    OUTPUT:
    
    INTEGER 10
    FLOAT 4.1
    FLOAT 91.1
    INTEGER 1000
    '''