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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_included_databases(self):
 """Return the databases we want to include, or empty list for all. """

        databases = set()
        databases.update(self._plain_db.keys())

        for _, namespace in self._regex_map:
            database_name, _ = namespace.source_name.split(".", 1)
            if "*" in database_name:
                return []
            databases.add(database_name)

        return list(databases)