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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 get_available_references(self, datas):
 """ Get available manifest reference names. Every rules starting with prefix from ``nomenclature.RULE_REFERENCE`` are available references. Only name validation is performed on these references. Arguments: datas (dict):
 Data where to search for reference declarations. Returns: list: List of every available reference names. This is the real name unprefixed. """

        names = []

        for k, v in datas.items():
            if k.startswith(RULE_REFERENCE):
                names.append(k[len(RULE_REFERENCE)+1:])

        return names