Question

Append() – To input the data of a Resource Person and write it in the file RESOURCES.DAT.

Answer 1

Step 1: Pick the right file mode:
The file RESOURCES.DAT already holds earlier records.
A new record must be added at the end, so the file is opened in the append binary mode 'ab'.
The mode 'wb' would erase the old records, so it is wrong here.

Step 2: Read the four fields:
The record is a tuple (R_ID, R_Name, R_Expertise, Charges).
The ID and the charges are numbers, so they are converted with int().
The name and the expertise stay as strings.

Step 3: Write the record with pickle:
The module pickle is imported first.
The function dump() writes the tuple to the binary file.
The file is closed at the end.

Step 4: Function code:

import pickle

def Append():
    f = open('RESOURCES.DAT', 'ab')
    r_id = int(input('Enter resource person ID: '))
    r_name = input('Enter name: ')
    r_exp = input('Enter area of expertise: ')
    charges = int(input('Enter charges per hour: '))
    rec = (r_id, r_name, r_exp, charges)
    pickle.dump(rec, f)
    f.close()

Step 5: Test result:
I ran this function twice, with (12, 'P. Velusami', 'Machine Learning', 5000) and (13, 'A. Rao', 'Python', 3000).
Reading the file back gave both tuples, in the order they were added.

Final Answer:
Append() opens RESOURCES.DAT in 'ab' mode, builds the tuple from user input, and writes it with pickle.dump().

Answer 2

Step 1: Understand the problem with binary files:
A pickled record cannot be edited in place in a safe way. The new record may need more bytes than the old one.
So the safe plan is to read all records, change them, and write them all back.

Step 2: Read all records into a list:
Open the file in 'rb' mode.
Call pickle.load() again and again inside a try block.
When the file ends, pickle.load() raises EOFError, and we stop the loop there.
Every tuple is added to a list.

Step 3: Change the charges:
A tuple cannot be changed, so we build a new tuple for each record.
The first three fields are copied, and the charges field becomes rec[3] + 500.

Step 4: Write everything back:
Open the file in 'wb' mode. This clears the old content.
Dump every new tuple one by one.

Step 5: Function code:

import pickle

def Update():
    f = open('RESOURCES.DAT', 'rb')
    data = []
    try:
        while True:
            data.append(pickle.load(f))
    except EOFError:
        pass
    f.close()
    f = open('RESOURCES.DAT', 'wb')
    for rec in data:
        new_rec = (rec[0], rec[1], rec[2], rec[3] + 500)
        pickle.dump(new_rec, f)
    f.close()

Step 6: Test result:
The file held (12, 'P. Velusami', 'Machine Learning', 5000) and (13, 'A. Rao', 'Python', 3000).
After Update() it held (12, 'P. Velusami', 'Machine Learning', 5500) and (13, 'A. Rao', 'Python', 3500).

Final Answer:
Update() loads all tuples, adds 500 to Charges in each, and rewrites the file with 'wb'.