:::4. Exit the ipython3 shell, download the checking script and check your work. Enter the following commands from the bash shell.<source>

:::5. Before proceeding, make certain that you identify any and all errors in lab3b.py. When the check script tells you everything is ok before proceeding to the next step.

:::5. Exit the ipython3 shell, download the checking script and check your work. Enter the following commands from the bash shell.<source>

:::6. Before proceeding, make certain that you identify any and all errors in lab3c.py. When the check script tells you everything is ok before proceeding to the next step.

:'''Perform the Following stepsSteps'''

:#Start the ipython3 shell<source>

 :#Create a few lists with different values: list1 contains only integers, list2 contains only strings, list3 contains a combination of both.<source>

 :#The best way to get individual items from a list is using the list index. The index is a number starting from 0 to (number_of_items - 1), the index starts counting at 0.<source>

 :#Instead of just getting the first and last, lists can give ranges of items. <source>

 :#Lists can also contain other lists. This means lists can contain: lists and strings and integers all together. <source>

 :#This list still only has 3 index locations. Each index points to another list. <source>

 :#To access a list inside another list, a second index is needed. Spend some time trying out the syntax and try and navigate to a specific spot in the list.<source>

 :#Using different items from different lists to create new lists.<source>

'''lab3ePractice Using Functions and Using the List Index''':'''Perform the Following Instructions''':#Create the '''~/ops435/lab3/lab3e.py''' script. The purpose of this script is to have a number of functions that output a different part of the list. Each function will return either a single item from the list OR will create a new list and return the entire new list.  :#The template function names and boiler plate if statement:<source>

 :::*The script should have a '''Shebang line''':::*The script should have a list called my_list:::*The list my_list should have the values: 100, 200, 300, 'six hundred':::*The script should have a function called give_list() which returns a list:::*The script should have a function called give_first_item() which returns a string:::*The script should have a function called give_first_and_last_item() which returns a list:::*The script should have a function called give_second_and_third_item() which returns a list  :::3. Sample Run 1:<source>

 :::4. Sample Import 1:<source>

  :::5. Exit the ipython3 shell, download the checking script and check your work. Enter the following commands from the bash shell.<source>

:::6. Before proceeding, make certain that you identify any and all errors in lab3e.py. When the check script tells you everything is ok before proceeding to the next step. 

:'''Perform the Following Steps:''':#First start with the smallest change. Change a single item at a single point in a list.<source>

 :#Now lets use the dir() and help() functions to see what functions and attributes lists have. The help() function will also give us tips on how to use some functions.<source>

  :#Next search and find more information on a number list functions for changing lists.<source> 

 :#Using Python functions we can get more information out of lists.<source>

 :#Now on to some of the more powerful features of Python lists. Searching for values inside lists and finding locations of values in a list. The index() function allows searching inside a list for a value, it will return the index number of the first occurence. <source>

 :#The problem that comes up here is if the item searched for doesn't exist, Python will throw a error. Lets make sure it exists before asking for the index location. To find out if a value is in a list, just ask using a if statement, if the statement is True, then the value is found in the list.<source>

This final section explains the best part about lists. The ability to quickly loop through every value in the list. '''For loops''' have a set number of times they loop. The '''for loop''' will one by one run all indented code for each item in the list.  :'''Perform the Following Steps''' :#The '''for loop''' will create a new variable that contains the value from the list of the current iteration.<source>

 :#Now instead of running functions over and over, from our previous sections, we can put them in a loop. The next sequence of code will apply a function to every item in the list.<source>

 :#But this only prints out each new value. Lets try making a new function that loops through lists, squares the values, and returns a new list.<source>

:#The above is just one example of quick, powerful, for loops mixed with lists. But be careful when passing lists into functions. When you give a function a list, it is the actual list reference and NOT a copy. This means a function can completely change the list without making a new list. While you do have to be careful this is also useful, a function can modify any given list, without have to return or store it.<source>

'''lab3fPractice Functions, Lists, Loops''':'''Perform the Following Instructions:''':#Create the '''~/ops435/lab3/lab3f.py''' script. The purpose of this script is to use functions to modify items inside a list.  <source>

:::*The script should have a '''Shebang line''':::*The list '''my_list''' should have the values: '''1, 2, 3, 4, 5''':::*The script should have a function called add_item_to_list(my_list) :::*The script should have a function called remove_items_from_list(my_list, items_to_remove) :::*The function add_item_to_list(my_list) takes a single argument which is a list. This function will look at the value of the last item in the list, it will then append a new value that is +1 bigger then the previous number. This function modifies the list without returning any value:::*The function remove_items_from_list(my_list, list_of_numbers_to_remove) takes two arguments, a list, and a list of numbers to remove from the list. This function will then check if those items are in the list, if they are it will remove them. This function modifies the list without returning any value. :::2. Sample Run 1:<source>

 :::3. Sample Import 1:<source>

 :::4. Exit the ipython3 shell, download the checking script and check your work. Enter the following commands from the bash shell.<source>

:::5. Before proceeding, make certain that you identify any and all errors in lab3f.py. When the check script tells you everything is ok before proceeding to the next step.