Write a program in Python that reads in a word or a sentence. The program should then print the word out gradually, i.e. add one letter in each line, and then make the word disappear one letter at a time (letters from the left being replaced with spaces). See examples for a detailed explanation. (hint: it's easiest to solve this in two separate parts, first make the word appear, and then disappear) --------------------- Examples: Write a word: abcd a ab abc abcd bcd cd d Write a word: testing t te tes test testi testin testing esting sting ting ing ng g