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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 _dump(self, tree):
 """ Run a DUMP statement """

        schema = []
        if tree.tables:
            for table in tree.tables:
                desc = self.describe(table, refresh=True, require=True)
                schema.append(desc.schema)
        else:
            for table in self.describe_all():
                schema.append(table.schema)

        return "\n\n".join(schema)