Add Page Iterator support

[shemogumbe]

Page Iterator For Python

- Define a callback function

def callback(items):
            for i in items:
                print(dir(i))
                print("--------------------------")

- Instantiate page iterator

page_iterator = PageIterator(paginated_response, client.request_adapter)

       page_iterator = PageIterator(messages, client.request_adapter)
       

Page Iterator functions and fields

      page_iterator = PageIterator(messages, client.request_adapter)
        print(
            f"Current page odata next link - {page_iterator.next_link}"
        )  # https://graph.microsoft.com/v1.0/users/7dbd310d-1148-44ff-8e68-1207f287c752/messages?%24top=10&%24skip=10

        print(
            f"Current page value - {type(page_iterator.current_page.value)}"
        )  #  an iterable list of model objects - remove type to see actual list or loop through it
        for message in page_iterator.current_page.value:
            print(f"Message - {message.subject}")

        # print(messages)

        print(f"Has next - {page_iterator.has_next}")
        print(f"Headers - {page_iterator.headers}")
        print(f"Request Options - {page_iterator.request_options}")
        print(f"Page Iterator Pause Index - {page_iterator.pause_index}")

        next_page = await page_iterator.next()  # uses fetch next page method
        # Next page - value and next link
        print(f"Next page Value  -{type(next_page.value)}")  #  an iterable list of model objects
        # does the next page have a next link
        print(
            f"Next page next link - {next_page.odata_next_link}"
        )  # https://graph.microsoft.com/v1.0/users/7dbd310d-1148-44ff-8e68-1207f287c752/messages?%24top=10&%24skip=20

        print("===============Iterating=================")
        page_iterator.iterate(callback(messages.value))  # uses enumerate method