Python: Ask to input again if "Enter" key is pressed without entering anything

Question

Everything works fine but if I press "Enter" without entering anything. It shows error! Is there any way to ask user to input again till a valid input is given. More specifically, to ask user input again if just "Enter" is pressed.

def dice():
user = input("Do you want to roll the dice? ")
while user[0].lower() == 'y':
 num = randrange(1, 7)
 print("Number produced: ", num)
 user = input("Do you want to roll the dice? ")

When "Enter" is pressed, following error shows

Do you want to roll the dice? 
Traceback (most recent call last):
File "C:/Users/a/Documents/Code/Learning_Python/dice_rolling_simulator.py", line 12, in <module>
dice()
File "C:/Users/a/Documents/Code/Learning_Python/dice_rolling_simulator.py", line 6, in dice
while user[0].lower() == 'y':
IndexError: string index out of range

Answer 1

While loop to ask again and again.

Xin = input("blah blah blah")
while Xin == "":
 Xin = input ('blah blah blah')

Answer 2

Use user in the condition of the while. This takes advantage of the facts that empty strings are evaluated to False and that the boolean operators in Python are short-circuited (if user is False then user[0].lower() == 'y' won't be evaluated, hence no IndexError will be raised):

while user and user[0].lower() == 'y':

Answer 3

Yes..! it is possible.

def dice():
 i = 1;
 while i:
 user = input("Do you want to roll the dice? ")
 if user != None:
 i = 0
 while user[0].lower() == 'y':
 num = randrange(1, 7)
 print("Number produced: ", num)

Answer 4

You need to rephrase it. Here's the whole code with comments and imports.

#importing random for randrange
import random
#defining rolling mechanism
def dice():
 #looping so that you can keep doing this
 while True:
 #asking for input
 user = input("Do you want to roll the dice? ")
 #if the user says 'y':
 if user.lower() == 'y':
 #it picks a random number from 1 to 6 and prints.
 num = random.randrange(1, 7)
 print("Number produced: ", num)
 #if not it will print that it doesn't understand the input and loop
 else:
 print("We don't understand your answer.")
dice()