himanshu1295/python_4

Mapping key-values to Dictionary data structures in Python

Lab Instructions: Mapping key-values to Dictionary data structures

So far you have learned that Python has different techniques to modify a given iterator sequence such as list or dictionary using comprehensions,
map() function and so on. Now you will be utilising what you have learned. Let’s say you have a list of employee data for the Little Lemon company.
You want to create login accounts for the employees and you will create usernames for these employees in the first example.

You also want to update the roster for these employees on the calendar and want easy access to their initials and employee IDs, as they are all unique.
To get that, in the second example, you will create a dictionary with the required information.

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Exercise Instructions

1. Open the comprehensions.py file

2. Implement the to_mod_list() function by using the map() function to apply mod() to all elements within employee_list.
   Assign the result of it to a new variable called map_emp. Convert map_emp to a list and return it.

   • The mod() function returns a string value for example such as “Lisa_Cold Storage” from the dictionary passed to it.
     
     

3. At this point you should have a list of the values such as: “Lisa_Cold Storage” mentioned above.
   But that is no good for a username with the whitespace present in it.

   • Implement the generate_usernames() method by using list comprehension and the replace() over mod_list
     to replace all spaces (" ") with underscores ("_").
   • Return the resulting list.
     
     

4. We want to create a dictionary that stores employees' first initials and IDs.

   • Implement map_id_to_initial() by using dictionary comprehension over the employee_list to create a dictionary
     where each key is the first letter of an employee's name and the value is the employee's ID.
     
     

5. Run the script by opening the terminal and executing the command:

   python3 comprehensions.py