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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:

async def update(self):
    '''
    reload all cached information

    |coro|

    Notes
    -----
    This is a slow process, and will remove the cache before updating.
    Thus it is recomended to use the `*_force` properties, which will
    only update the cache after data is retrived.
    '''
    keys = self.extras.keys()
    self.extras = {}
    for key in keys:
      try:
        func = getattr(self, key, None)
        if callable(func):
          func()
      except:
        pass