'read all pages'

def read_all_tasks(self, st=0):

    all_tasks = []
    (tasks, next_link) = self.read_task_page(st)
    all_tasks.extend(tasks)
    while next_link:
        (tasks, next_link) = self.read_task_page_url(next_link)
        all_tasks.extend(tasks)
    for (i, task) in enumerate(all_tasks):
        task['#'] = i
    return all_tasks
