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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 alias(self):
 """ If the _alias cache is None, just build the alias from the item name. """

        if self._alias is None:
            if self.name in self.aliases_fix:
                self._alias = self.aliases_fix[self.name]
            else:
                self._alias = self.name.lower()\
                                  .replace(' ', '-')\
                                  .replace('(', '')\
                                  .replace(')', '')
        return self._alias