Grocery apps

A4p_input.csv and A4s_input.csv are two files that respectively record the purchase and sales orders of an online store. These transactions have not been properly sorted according to time. Please write a general program to accept the data. You should view both files using Notepad or Word, because Excel may reformat the date-time. Do NOT use the date-time import, but write your own Python codes to process the date-time column as some may be out of range. Some tips:

Use open() and readlines() to read csv files

Use split() to separate items in a string, strip() to remove spaces

Remember to convert string to integer by calling e.g. int(12) Parts of the input: A4p_input:

date/time	item name	cost per unit	units purchased
########	watermelon	10	10
########	apple	5	2
########	durian	20	3
########	orange	8	2
########	apple	5	1
########	orange	7	2
########	watermelon	5	1
########	watermelon	1	4
########	apple	13	6
########	apple	18	5
########	watermelon	13	9
########	apple	10	9
########	apple	2	2
########	orange	5	2
########	apple	13	9
########	watermelon	6	9
########	watermelon	16	2
########	durian	19	5
########	watermelon	12	10

A4s_input:

date/time	item name	price per unit	units sold
########	watermelon	17	4
########	durian	21	5
########	apple	15	4
########	durian	32	5
########	durian	12	1
########	apple	23	5
########	apple	21	3
########	orange	23	3
########	durian	32	1
########	apple	32	1
########	apple	11	1
########	apple	38	1
########	durian	33	3
########	orange	10	3
########	watermelon	26	5
########	orange	11	5
########	orange	35	10
########	apple	30	4
########	watermelon	19	4

Question:

Determine the profit margin (i.e. average profit/average cost) for each item.