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CBSE · 083Class XII · 2023Section E4 marks

Question 35(1)

30 March 2023 · Computer Science (083)

Shreyas is a programmer who has been given the task of writing a function write_bin() to create a binary file Cust_file.dat containing customer records — customer number (c_no), name (c_name), quantity (qty), price (price) and amount (amt).

The function accepts c_no, c_name, qty and price. If qty is less than 10, it prints 'Quantity less than 10 ..... Cannot SAVE'. Otherwise it computes amt = price * qty and writes the record (as a list) to the binary file.

python
import pickle

def write_bin():
    bin_file = __________              # Statement 1
    while True:
        c_no = int(input("enter customer number"))
        c_name = input("enter customer name")
        qty = int(input("enter qty"))
        price = int(input("enter price"))
        if __________ :                # Statement 2
            print("Quantity less than 10..Cannot SAVE")
        else:
            amt = price * qty
            c_detail = [c_no, c_name, qty, price, amt]
            __________                 # Statement 3
            ans = input("Do you wish to enter more records y/n")
            if ans.lower() == 'n':
                __________             # Statement 4
    ______________                     # Statement 5

______________                         # Statement 6

Answer the following : (i) Write the correct Statement 1 to open 'Cust_file.dat' for writing. (ii) Write Statement 2 to check whether qty is less than 10. (iii) Write Statement 3 to write data to the binary file and Statement 4 to stop further processing if the user does not wish to enter more records.

Answer

(i) Statement 1 —

python
bin_file = open("Cust_file.dat", "wb")

("ab" mode is also accepted.)

(ii) Statement 2 —

python
qty < 10

(iii) Statement 3 —

python
pickle.dump(c_detail, bin_file)

Statement 4 —

python
break

Explanation

Statement 1 opens the file in binary-write mode. Statement 2 is the condition that flags a too-small quantity. Statement 3 serialises the record list to the binary file with pickle.dump. Statement 4 exits the while loop when the user has no more records to enter.