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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def request_videos(blink, time=None, page=0):
 """ Perform a request for videos. :param blink: Blink instance. :param time: Get videos since this time. In epoch seconds. :param page: Page number to get videos from. """

    timestamp = get_time(time)
    url = "{}/api/v2/videos/changed?since={}&page={}".format(
        blink.urls.base_url, timestamp, page)
    return http_get(blink, url)