we can think of the two continue statements as helping us refine the set of lines which are "interestingto us and which we want to process some more line which has no words is "uninterestingto us so we skip to the next line line which does not have "fromas its first word is uninteresting to us so we skip it the program as modified runs successfullyso perhaps it is correct our guardian statement does make sure that the words[ will never failbut perhaps it is not enough when we are programmingwe must always be thinking"what might go wrong?exercise figure out which line of the above program is still not properly guarded see if you can construct text file which causes the program to fail and then modify the program so that the line is properly guarded and test it to make sure it handles your new text file exercise rewrite the guardian code in the above example without two if statements insteaduse compound logical expression using the or logical operator with single if statement glossary aliasing circumstance where two or more variables refer to the same object delimiter character or string used to indicate where string should be split element one of the values in list (or other sequence)also called items equivalent having the same value index an integer value that indicates an element in list identical being the same object (which implies equivalencelist sequence of values list traversal the sequential accessing of each element in list nested list list that is an element of another list object something variable can refer to an object has type and value reference the association between variable and its value exercises exercise find all unique words in file shakespeare used over , words in his works but how would you determine thathow would you produce the list of all the words that shakespeare usedwould you download all his workread it and track all unique words by handlet' use python to achieve that instead list all unique wordssorted in alphabetical orderthat are stored in file romeo txt containing subset of shakespeare' work to get starteddownload copy of the file www py com/code /romeo txt create list of unique wordswhich will contain the final result write program to open the file romeo txt and read it line by line for each