I forgot the .join builtin. To use list comprehension was way good! I need to learn it.

You're not supposed to paste solutions here.

You're not supposed to paste solutions here.

def digital_root(n):

sum = 0
temp = n #temparory variable to store n
while temp > 9:
    for i in str(temp): #convert the integer to a string to iterate through
        sum += int(i)
    temp = sum
    #change the sum back to 0 for further iterations
    sum = 0

return temp

This was my solution to the digital root problem, this is not the most efficient solution. Can anyone post more efficient solutions to this problem?

def create_phone_number(n):

if len(n) == 10:
    phone_number = ''.join(str(i) for i in n)
    newPhone = "(" + phone_number[0:3] + ")" + ' ' + phone_number[3:6] + '-' + phone_number[6:12]
return newPhone

This was a solution to the phone number problem, but I believe there are so many more efficient solutions, help me improvise this solution.

Please don't post solutions in kata's Discourse. Use Solutions section to discuss it. Even there, use spoiler flag when appropiate.