Add object validating if it exists

Question

I am creating these two methods in which the first worth the existence of a vehicle from your name. In the second, it is intended to add a new vehicle, validating first, if there is a vehicle with a given name, to avoid duplication of results. However, I always get the error described.

What can I do to prevent that from happening? Just the attribute preco_base is mutable

def exists_viatura(self, nome):
    for v in self.gestor:
        if v.nome == nome:
            return True
        else:
            print("Não existe nenhuma viatura")

def add_viatura(self, new_v):
    for v in self.gestor:
        new_v = Viatura(new_v.nome, new_v.modelo, new_v.tipo_electrica, new_v.preco_base)
        if g.exists_viatura(new_v.nome):
            print("Já existe uma viatura com esse nome")
    self.gestor.append(new_v)

Error:

Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "C:/Users/sandr/PycharmProjects/projecto/Classes_Projecto.py", line 189, in add_viatura
    new_v = Viatura(new_v.nome, new_v.modelo, new_v.tipo_electrica, new_v.preco_base)
AttributeError: 'str' object has no attribute 'nome'

Answer 1

In Python to check if an object exists in a list is very simple. I believe that in your code would look like this:

def add_viatura(self, new_v):
    # verifica se existe a viatura na lista 'gestor'
    viatura_existe = new_v in self.gestor
    if viatura_existe:
        print("Já existe uma viatura com esse nome")
    else:
        self.gestor.append(new_v)