'Find alternative keys to use in generated redirects
Returns:
Set of possible redirect entries'

def parse_alternative_keys(self):

    self.alternative_keys = set()
    if (('.' in self.key) and (self.entry_type == 'A')):
        key_arr = self.key.split('.')
        method_name = key_arr[(-1)]
        key_arr_len = len(key_arr)
        self.alternative_keys.add(method_name)
        if (key_arr_len >= 3):
            for l in range((key_arr_len - 1)):
                permutations = itertools.permutations(key_arr[:(key_arr_len - 1)], (l + 1))
                for k in permutations:
                    new_key = '{}    {}'.format('    '.join(k), method_name)
                    self.alternative_keys.add(new_key)
        else:
            package_name = key_arr[0]
            new_key = '{}    {}'.format(package_name, method_name)
            self.alternative_keys.add(new_key)
    return self.alternative_keys
