Variables in Python: Add and change variables -

i making game in python, , want add store.

i want variable. know how add variables, , how change them, not how increase or decrease variable.

i have never used variables before. have read it, don't remember it.

def level1(): os.system('cls') gold = 500 print print 'you have currently', print (gold), print 'gold' time.sleep(3) level2()  def level2(): print print 'congratulation! completed quest! received 200 gold.' time.sleep(2) gold =+ 200 print 'you have now', print (gold), print 'gold.' time.sleep(5) 

and result is:

you have 500 gold

congratulation! completed quest! received 200 gold. have 200 gold.

i tried gold + 200, gold += 200, , gold =+ 200, last 1 worked.

i tried

print 'you have now' + gold + 'gold' 

but didn't work reason. tried

print 'you have now' + (gold) + 'gold' 

i not quite sure what's wrong here, , appreciate can get!

thank much.

edit:

i forgot add huge part of question. sorry that!

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in store, sell multiple items different prices. not of items available in beginning of game. therefore want item check how gold user have. if user have under x gold, can't buy item.

if level have reached level 04, specific item unlocked.

it should gold += 200 , not gold =+ 200.

secondly, seems gold variable local each function, i.e. assigning gold 500 in level1() not set value in level2. need either pass in arguments, or have global.

to pass arguments:

def level1(gold) :   # stuff here   level2(gold)  def level2(gold) :   # stuff here  # entry point of application if __name__ == "__main__" :   # initialize `gold` here   gold = 500   level1(gold) 

to use global instance:

# global variable  gold = 500  def level1() :   # specify want use global instance of gold   global gold   # stuff here  def level2() :   global gold   # stuff here