Output showing "None" in Terminal

[Py Noob]

Hi!

i'm new to python and would like some help with something i was working on
from a tutorial. I'm using VScode with 3.7.0 version on Windows 7. Below is
my code and the terminal is showing the word "None" everytime I execute my
code.

Many thanks!

print("Conversion")

def km_mi():
    return answer

selection = input("Type mi for miles or km for kilometers: ")

if selection == "mi":
    n = int(input(print("Please enter distance in miles: ")))
    answer = (1.6*n)
    print("%.2f" % answer, "miles")

else:
    n = float(input(print("Please enter distance in kilometers: ")))
    answer = (n/1.6)
    print("%.2f" % answer, "kilometers")

answer = km_mi