python - Need to fix a function to turn an even number into the next highest odd number -

this current code:

def main(): print() print("program draw triangles.") print("written josh sollenberger.") print() triangle = '' while(true):      choice = getchoice()     if choice == "1":         triangle = triangle + makestripeup()     if choice == "2":         triangle = triangle + makestripedown()     if choice == "3":         print(triangle)     if choice == "4":         triangle = triangle + "\n"     if choice == "5":         break  def makestripeup():     triangle = ''     base = getbase()     blanks = int(input("enter number of blanks preceding each line: "))     character = input("enter character used draw: ")     in range(base//2 + 1):         triangle = triangle + ((' ' *(i+blanks) + character * (base - (2*i)))) +'\n'     return triangle  def makestripedown():     triangle = ''     base = getbase()     blanks = int(input("enter number of blanks preceding each line: "))     character = input("enter character used draw: ")     in range(base//2 + 1, -1, -1):         triangle = triangle + ((' ' *(i+blanks) + character * ( base - (2*i)))) +'\n'     return triangle   def getbase():         base = int(input("enter size of base: "))         if base % 2 == 0:             base = base + 1         else:             return base 

my program makes triangles out of users input. need base odd number prevent triangle looking (with base of 10):

    **    ****   ******  ******** ********** 

when enter 10, 'nonetype' error i'm assuming referring base. if use odd number, 11, works should.

     *     ***    *****   *******  ********* *********** 

is there needs changed in getbase() function?

you have evenness test backwards; if base % 2 == 1, base odd.

try instead

def get_base():     base = int(input("enter size of base: "))     if not base % 2:         # base         base += 1     return base