Copilot solution:

def mapper(record):
    record = record.strip().split(",")
    if record[0] == "Employee":
        mapReducer.emitIntermediate(record[2], ("Employee", record[1]))
    elif record[0] == "Department":
        mapReducer.emitIntermediate(record[1], ("Department", record[2]))
        

def reducer(key, list_of_values):
    employee_records = [v for v in list_of_values if v[0]=="Employee"]
    department_records = [v for v in list_of_values if v[0]=="Department"]
    
    for e in employee_records:
        for d in department_records:
            mapReducer.emit((key, e[1], d[1]))

from collections import OrderedDict import sys

class MapReduce: def init(self): self.intermediate = OrderedDict() self.result = []

def emitIntermediate(self, key, value):
    self.intermediate.setdefault(key, [])       
    self.intermediate[key].append(value)

def emit(self, value):
    self.result.append(value) 

def execute(self, data, mapper, reducer):
    for record in data:
        mapper(record)

    for key in self.intermediate:
        reducer(key, self.intermediate[key])

    self.result.sort()
    for item in self.result:
        print item

mapReducer = MapReduce()

def mapper(record): #Start writing the Map code here fields = record.replace('\n', '').split(',')

if fields[0] == 'Employee':
    person_name = fields[1]
    ssn = fields[2]
    mapReducer.emitIntermediate(ssn, (fields[0], person_name))
else:
    ssn = fields[1]
    department_name = fields[2]
    mapReducer.emitIntermediate(ssn, (fields[0], department_name))

def reducer(key, list_of_values): #Start writing the Reduce code here person_names = [] department_names = [] for label, value in list_of_values: if label == 'Employee': person_names.append(value) else: department_names.append(value)

for person_name in person_names:
    for department_name in department_names:
        mapReducer.emit((key, person_name, department_name))

if name == 'main': inputData = [] for line in sys.stdin: inputData.append(line) mapReducer.execute(inputData, mapper, reducer)

Here is Map Reduce Advanced - Relational Join problem solution - https://www.gyangav.com/2022/11/hackerrank-map-reduce-advanced-relational-join-problem-solution.html