feat: Added Week3 and Week4 tasks

Week3_4/armstrong_check.py

Week3_4/calculator.py

Week3_4/case_det.py

Week3_4/concatenate_dict.py

Week3_4/count_a.py

Week3_4/letter_common.py

Week3_4/list_int.py

Week3_4/list_manipulation.py

Week3_4/prime_det.py

Week3_4/record_avgtemp.py

Week3_4/sets_manipulation.py

Week3_4/sort_names.py

Week3_4/temperature_dic.py

Week3_4/week3_4.docx