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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 is_valid_single_address(self, single_address):
 """Check if a potentially ambiguous single address spec really exists. :param single_address: A SingleAddress spec. :return: True if given spec exists, False otherwise. """

    if not isinstance(single_address, SingleAddress):
      raise TypeError(
        'Parameter "{}" is of type {}, expecting type {}.'.format(
          single_address, type(single_address), SingleAddress))

    try:
      return bool(self.scan_specs([single_address]))
    except AddressLookupError:
      return False