Generate a Python user-defined function that accepts a string of any length and first displays the string followed by a newline followed by a horizontal\ frequency graph of only lowercase ALPHABETIC letters in the string (in alphabetical order). Spaces and all non-alphabetic characters are to be ignored! The function prototype MUST be: def IcFrequency (userString) For example, the function call: IcFrequency("This is a Python test 123!") would display: This is a Python test 123! a=1* e=1* h=2** n=1* 0=1* s=3 t=3*** *** y=1* HINT: Consider using Python's upper(), lower(), and ord() functions and string.ascii_lowercase to complete your solution.