Чтение из бинарного файла

import pickle
from datetime import *
 
def AddToFile(fileName):
    file = open(fileName, 'wb')
    products = []
    flag = True
    while flag:
        product = {
            "name":str(input("Name: ")),
            "firstDate":str(input("Date of issue: ")),
            "lastDate":str(input("Expiry date: "))
        }
        print("Added")
        products.append(product)
        ans = str(input("Continue?(Y/N) "))
        if ans == "N" or ans == "n":
            flag = False
    pickle.dump(products,file)
    file.close()
    return products
 
 
def output_file(fileName):
    file = open(fileName, 'rb')
    products = pickle.load(file)
    for product in products:
        print(product["name"]+ ' ' + product["firstDate"] + ' ' + product["lastDate"] + ' ' )
    file.close()
 
 
def isOverdue(product):
    today = date.today()
    dayToday = today.strftime("%d.%m.%Y")
    lastdate = product["lastDate"]
    t1 = datetime.strptime(dayToday, "%d.%m.%Y")
    t2 = datetime.strptime(lastdate, "%d.%m.%Y")
    day = t2-t1
    Days = day.days
    if Days >= 0:
        return True
    else:
        return False
 
def datesDiff(product):
    firstdate = product["firstDate"]
    lastdate = product["lastDate"]
    t1 = datetime.strptime(firstdate, "%d.%m.%Y")
    t2 = datetime.strptime(lastdate, "%d.%m.%Y")
    day = t2-t1
    return day.days
def allDiffs(products):
    diffs = []
    for product in products:
        day = datesDiff(product)
        diffs.append(day)
    return diffs
def TwoFiles(fileP, fileL, products, diffs):
    file1 = open(fileP,'wb')
    file2 = open(fileL,'wb')
    for i in range(0, len(products)):
        if isOverdue(products[i]):
            continue
        else:
            if diffs[i] <=5:
                pickle.dump(products[i],file1)
            else:
                pickle.dump(products[i],file2)
    file2.close()
    file1.close()
 
    fileName = "NewFilePy.dat"
products = AddToFile(fileName)
dateDiffs = allDiffs(products)
fileP = "Perishable.dat"
fileL = "Long_term.dat"
TwoFiles(fileP,fileL,products,dateDiffs)
output_file(fileName)
print("Perishable:")
output_file(fileP)
print("Long-term:")
output_file(fileL)

def TwoFiles(fileP, fileL, products, diffs):
    file1 = open(fileP,'wb')
    file2 = open(fileL,'wb')
    perishProds = []
    longTProds = []
    for i in range(0, len(diffs)):
        if isOverdue(products[i]):
            continue
        else:
            if diffs[i] <=5:
                perishProds.append(products[i])
            else:
                longTProds.append(products[i])
 
    pickle.dump(perishProds,file1)
    pickle.dump(longTProds,file2)
    file2.close()
    file1.close()

return Days >= 0