def fibgenerator(firstSeedNum, secondSeedNum):
                                while True:
                                    temp = firstSeedNum + secondSeedNum
                                    yield temp  # this statement suspends the function execution, until 'next' is called again
                                    firstSeedNum  = secondSeedNum
                                    secondSeedNum = temp
    
                                # two step process, create a generator object and iterate over the returned generator object. Creating generator
    
                                a = fibgenerator(0, 1) # this creates a generator object, that can be iterated to get the next element
                                # the above statement just packed the arguments and keep it ready for iteration
                                b = fibgenerator(3, 27) # this creates another generator object, with different initial seed numbers
                                for i in range(10):
                                print(next(a)) # this is a generator that will generate elements infinitely, since, there is a while loop, that's always true
                                            # when the next is called for the first time, temp is intermittently returned with function execution suspension
                                            # only when the next is called for the second time, the function is reentered and start from the very next statement, from where it left off
                                            # you will SURPRISED to read about coroutine, coyield and coreturn -- which were added in C++ 20 [we are seriously outdated, look at the memory layout of these features]
                                for i in range(20):
                                print(next(b))
    
                                c = list(a) # both these lines will cause you machine to hang,
                                d = list(b) # because, generator object will be iterated forever to fill up the list. So caution - advised.
                                # Apart from the above mentioned drawback, generators just remembers, only the required information to move ahead with execution.
                                # for our examples -- first two seed elements will be remembered in a and b respectively.