isValid = False
while isValid != True:
gameStr = raw_input ("Choose a space to place the card: ")
#the below makes sure that the input is a digit
if gameStr.isdigit() != True:
print "Not valid input. Please input a digit."
isValid = False
continue
gameNum = int(gameStr)
#the below makes sure input is between 1 and 20
if gameNum <= 0 or gameNum > 20:
print "Not a valid space. Please choose again."
isValid = False
continue
#the below makes sure the user does not place a second card in any slot
if cardList[gameNum].get_val() != 0:
print "Space already taken. Please select a different space."
isValid = False
continue
#if we made it here, it's good
isValid = True