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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 interface_type(self):
 """ Get the CoRE Link Format if attribute of the resource. :return: the CoRE Link Format if attribute """

        value = "if="
        lst = self._attributes.get("if")
        if lst is None:
            value = ""
        else:
            value += "\"" + str(lst) + "\""
        return value