def eggs(someparameter):
    someparameter.append("hello")

spam =[1,2,3]
eggs(spam)
print(spam)

#imstead of reference the existing list, you can copy it.


import copy
spam=['A','B','C',1,2]
cheese=copy.deepcopy(spam)

print(spam)
print(cheese)

cheese[1]=42

print(spam)
print(cheese)
