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  <xs:element id="cstl_DerekMaetzoldTradingArrangementRSUsAndPSUsMember" abstract="true" name="DerekMaetzoldTradingArrangementRSUsAndPSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
