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				<link:definition>01009 - Schedule - Average Annual Total Returns {Transposed}</link:definition>
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				<link:definition>01020 - Document - Risk/Return Summary (MFS High Yield Pooled Portfolio) {Unlabeled}</link:definition>
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				<link:definition>01026 - Schedule - Average Annual Total Returns {Transposed}</link:definition>
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				<link:definition>01027 - Schedule - Risk Table {Transposed}</link:definition>
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				<link:definition>01028 - Document - Risk/Return Summary (MFS Municipal High Income Fund) {Unlabeled}</link:definition>
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				<link:definition>01035 - Schedule - Average Annual Total Returns {Transposed}</link:definition>
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				<link:definition>01036 - Schedule - Risk Table {Transposed}</link:definition>
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