in you learned about using for loops to execute block of code certain number of times technicallya for loop repeats the code block once for each item in list value for exampleif you ran this codefor in range( )print(ithe output of this program would be as follows this is because the return value from range( is sequence value that python considers similar to [ (sequences are described in "sequence data typeson page the following program has the same output as the previous onefor in [ ]print(ithe previous for loop actually loops through its clause with the variable set to successive value in the [ list in each iteration common python technique is to use range(len(somelist)with for loop to iterate over the indexes of list for exampleenter the following into the interactive shellsupplies ['pens''staplers''flamethrowers''binders'for in range(len(supplies))print('index str(iin supplies issupplies[ ]index in supplies ispens index in supplies isstaplers index in supplies isflamethrowers index in supplies isbinders using range(len(supplies)in the previously shown for loop is handy because the code in the loop can access the index (as the variable iand the value at that index (as supplies[ ]best of allrange(len(supplies)will iterate through all the indexes of suppliesno matter how many items it contains the in and not in operators you can determine whether value is or isn' in list with the in and not in operators like other operatorsin and not in are used in expressions and connect two valuesa value to look for in list and the list where it may be