Help me in solving PYTHONCH31 problem

help
,
1

My issue

return "This magical creature " + ", ".join(a) + “.”

My code

class Dragon:
    def __init__(self):
        self.can_fly = True
        self.breathes_fire = True

class Unicorn:
    def __init__(self):
        self.has_horn = True
        self.grants_wishes = True

class Mermaid:
    def __init__(self):
        self.swims_fast = True
        self.sings_beautifully = True

class HybridCreature(Dragon,Unicorn,Mermaid):
    def __init__(self):
        Dragon.__init__(self)
        Unicorn.__init__(self)
        Mermaid.__init__(self)
    def describe_abilities(self):
        a=[]
        if self.can_fly:
            a.append("can fly")
        if self.breathes_fire:
            a.append("breathes fire")
        if self.has_horn:
            a.append("has horn")
        if self.grants_wishes:
            a.append("grants wishes")
        if self.swims_fast:
            a.append("swims fast")
        if self.sings_beautifully:
            a.append("sings beautifully")
        #return "This magical creature " + ", ".join(a) +"."
        return "This magical creature " + ", ".join(a) + "."

def generate_magical_creature():
    # TODO: Create and return a HybridCreature object
    return HybridCreature()

if __name__ == "__main__":
    creature = generate_magical_creature()
    print(creature.describe_abilities())

Learning course: Python Coding Challenges
Problem Link: Create a Magical Creature Generator Practice Problem in Python Coding Challenges