Basic Python Message Decryption System

print("A = 1, B = 2, C = 3, D = 4, E = 5, F = 6, G = 7, H = 8, I = 9, J = 10, K = 11, L = 12, M = 13, N = 14, O = 15, P = 16, Q = 17, R = 18, S = 19, T = 20, U = 21, V = 22, W = 23, X = 24, Y = 25, Z = 26")
print("Enter your message!")
input()
#make as many inputs as you want, you can only do one letter per input or the decryption won't work
if input == "1":
    print("A")
if input == "2":
    print("B")
if input == "3":
    print("C")
if input == "4":
    print("D")
if input == "5":
    print("E")
if input == "6":
    print("F")
if input == "7":
    print("G")
if input == "8":
    print("H")
if input == "9":
    print("I")
if input == "10":
    print("J")
if input == "11":
    print("K")
if input == "12":
    print("L")
if input == "13":
    print("M")
if input == "14":
    print("N")
if input == "15":
    print("O")
if input == "16":
    print("P")
if input == "17":
    print("Q")
if input == "18":
    print("R")
if input == "19":
    print("S")
if input == "20":
    print("T")
if input == "21"
    print("U")
if input == "22"
    print("V")
if input == "23"
    print("W")
if input == "24"
    print("X")
if input == "25"
    print("Y")
if input == "26"
    print("Z")
#See the original encryption script here: https://pastebin.com/gpWreEPg