Python - Referencing lists in functions -

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• how clone or copy list? 14 answers

needless following code not work , fault or problem seems function not access or recognise list [cards]. on other hand if place list [cards] within function, code works perfectly. had assumed variables placed in main code global, , variables declared in function local.

#!/usr/bin/python  import random  cards = ['a︎♣︎︎', '2︎♣︎︎', '3︎♣︎︎', '4︎♣︎︎', '5︎♣︎︎', '6︎♣︎︎', '7︎♣︎︎', '8︎♣︎︎', '9︎♣︎︎', '10︎♣︎︎', 'j︎♣︎︎', 'q︎♣︎︎',          'k︎♣︎︎', 'a♠︎', '2♠︎', '3♠︎', '4♠︎', '5♠︎', '6♠︎', '7♠︎', '8♠︎', '9♠︎', '10♠︎', 'j♠︎',          'q♠︎', 'k♠︎', 'a︎♥︎', '2︎♥︎', '3︎♥︎', '4︎♥︎', '5︎♥︎', '6︎♥︎', '7︎♥︎', '8︎♥︎', '9︎♥︎', '10︎♥︎',          'j︎♥︎', 'q︎♥︎', 'k︎♥︎', 'a︎♦︎︎', '2︎♦︎︎', '3︎♦︎︎', '4︎♦︎︎', '5︎♦︎︎', '6︎♦︎︎', '7︎♦︎︎', '8︎♦︎︎', '9︎♦︎︎',          '10︎♦︎︎', 'j︎♦︎︎', 'q︎♦︎︎', 'k︎♦︎︎']  # define function   def sort_cards(hand):      temp = []     n in range(0, 7):         temp.append(cards.index(str(hand[n])))      # sort cards     temp.sort()     hand = []      # fetch card according index , assign hand     c in temp:         hand.append(cards[c])      return hand   # copy cards list working list  rem_cards = cards  # initiate players card list  player1 = [] player2 = [] player3 = []  # define variable # 7 cards per player  deal = 7  while deal != 0:      # card rem_cards , assign player1     card = rem_cards[random.randint(0, len(rem_cards) - 1)]     player1.append(card)     # remove card deck     rem_cards.remove(card)      card = rem_cards[random.randint(0, len(rem_cards) - 1)]     player2.append(card)     rem_cards.remove(card)      card = rem_cards[random.randint(0, len(rem_cards) - 1)]     player3.append(card)     rem_cards.remove(card)      deal -= 1   print(sort_cards(player1)) print(sort_cards(player2)) print(sort_cards(player3)) print("no of cards left in deck ", len(rem_cards)) 

any suggestions or concept wrong?

take @ comments:

# copy cards list working list  rem_cards = cards 

this code does not make copy of list, creates name, under original list accessed. whenever modify rem_cards, cards modified. thus, rem_cards.remove(card) removes card cards!

if want copy list, use copy.[deep]copy:

import copy  # copy cards list working list  rem_cards = copy.deepcopy(cards) # if cards contain other lists rem_cards = copy.copy(cards) # create simple shallow copy rem_cards = cards[:] # may create shallow copies without copy module