The Zen of Python

Gur Mra bs Clguba

str=input()
strlist=list(str)
for i in range(len(strlist)):
  if strlist[i]>='a' and strlist[i]<='z':
    if ord(strlist[i])+13<=122:
      strlist[i]=chr(ord(strlist[i])+13)
    else:
      strlist[i]=chr((ord(strlist[i])+13)%122+96)
  elif strlist[i]>='A' and strlist[i]<='Z':
    if ord(strlist[i])+13<=90:
      strlist[i]=chr(ord(strlist[i])+13)
    else:
      strlist[i]=chr((ord(strlist[i])+13)%90+64)
print("".join(strlist))