Switching between classes and passing results - python-3.x

Question

I am trying to add different PlugLead's to the PlugBoard and extract the combination. In the first class I am extracting the one letter from the list should they match or return the input. e.g.
lead = PlugLead("AG")
assert(lead.encode("A") == "G")
class PlugLead:
def __init__(self, c):
self.c = c
def encode(self, l):
c0 = self.c[0]
c1 = self.c[1]
if len(l) == 1 and c0 == l:
return c1
elif len(l) == 1 and c1 == l:
return c0
else:
return l
class Plugboard:
def __init__(self):
self.__head = 0
self.leads = []
self.c = []
def add(self, item):
if self.__head >= 10:
print("leads already got 10 items")
elif item in self.leads:
print(f"leads already have this item: {item}")
else:
self.leads.append(item)
self.__head += 1
return self.leads
def encode(self)
lines = plugboard.leads
for word in lines:
word = word.split(",")
PlugLead.encode(word)
In the second class I am trying to add multiple combinations and then at the end pass the one letter to see what its match is in the Class PlugLead however am not able to switch between the two. In the class PlugLead I have a add function that allows the different combinations to be added up to 10 and then I would like to encode from this list the combination of the pairs. e.g.
plugboard = Plugboard()
plugboard.add(PlugLead("SZ"))
plugboard.add(PlugLead("GT"))
plugboard.add(PlugLead("DV"))
plugboard.add(PlugLead("KU"))
assert(plugboard.encode("K") == "U")
assert(plugboard.encode("A") == "A")

Answer 1

if you want to use PlugLead("{balabala}"),you need use __new__ to return a dict when you create an instance, not __init__.
you want a key-value pair in Plugboard, it should be a dict not list
fix some other typo and bugs.
code:
class PlugLead:
def __new__(self, c):
return {c[0]:c[1]}
class Plugboard:
def __init__(self):
self.__head = 0
self.leads = {}
def add(self, item):
if self.__head >= 10:
print("leads already got 10 items")
elif list(item.keys())[0] in self.leads.keys():
print(f"leads already have this item: {item}")
else:
self.leads.update(item)
self.__head += 1
return self.leads
def encode(self,key):
if key in self.leads:
return self.leads[key]
elif key in self.leads.values():
return list(self.leads.keys())[list(self.leads.values()).index(key)]
return key
plugboard = Plugboard()
plugboard.add(PlugLead("SZ"))
plugboard.add(PlugLead("GT"))
plugboard.add(PlugLead("DV"))
plugboard.add(PlugLead("KU"))
plugboard.add(PlugLead("KU"))
assert(plugboard.encode("K") == "U")
assert(plugboard.encode("U") == "K")
assert(plugboard.encode("A") == "A")
print(plugboard.encode("K"))
print(plugboard.encode("U"))
print(plugboard.encode("A"))
result:
leads already have this item: {'K': 'U'}
U
K
A