DESCRIPTION: Task Given a string str, reverse it and omit all non-alphabetic characters. Example For str = "krishan", the output should be "nahsirk". For str = "ultr53o?n", the output should be "nortlu". Input/Output [input] string str A string consists of lowercase latin letters, digits and symbols. [output] a string def reverse_letter(string): #a 97 z 122 ans="" for i in string: if ord(i)>=97 ..