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  <xs:element id="sgp_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="sgp_TemporaryEquitySharesConversionOfConvertibleSecurities" abstract="false" name="TemporaryEquitySharesConversionOfConvertibleSecurities" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="sgp_TemporaryEquityValueConversionOfConvertibleSecurities" abstract="false" name="TemporaryEquityValueConversionOfConvertibleSecurities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sgp_PaymentsOfTemporaryEquityIssuanceCosts" abstract="false" name="PaymentsOfTemporaryEquityIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sgp_DeferredOfferingCostsIncurredButNotYetPaid" abstract="false" name="DeferredOfferingCostsIncurredButNotYetPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sgp_AssetsAndLiabilitiesLesseeTableTextBlock" abstract="false" name="AssetsAndLiabilitiesLesseeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="sgp_WorkingCapital" abstract="false" name="WorkingCapital" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sgp_ConstructionInProgressMachineryAndEquipmentMember" abstract="true" name="ConstructionInProgressMachineryAndEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_SoftwareMember" abstract="true" name="SoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_ConstructionInProgressLeaseholdImprovementsMember" abstract="true" name="ConstructionInProgressLeaseholdImprovementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_RedeemableConvertibleSeriesAPreferredStockMember" abstract="true" name="RedeemableConvertibleSeriesAPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_RedeemableConvertibleSeriesBPreferredStockMember" abstract="true" name="RedeemableConvertibleSeriesBPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_RedeemableConvertibleSeriesCPreferredStockMember" abstract="true" name="RedeemableConvertibleSeriesCPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_RedeemableConvertibleSeriesC1PreferredStockMember" abstract="true" name="RedeemableConvertibleSeriesC1PreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_RedeemableConvertibleSeriesC2PreferredStockMember" abstract="true" name="RedeemableConvertibleSeriesC2PreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_RedeemableConvertibleSeriesDPreferredStockMember" abstract="true" name="RedeemableConvertibleSeriesDPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_TemporaryEquityStockIssuedDuringPeriodValueNewIssuesPricePerShare" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodValueNewIssuesPricePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="sgp_TemporaryEquityNumberOfTranches" abstract="false" name="TemporaryEquityNumberOfTranches" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="sgp_UniversityOfColoradoLicenseAgreementMember" abstract="true" name="UniversityOfColoradoLicenseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sgp_LesseeNumberOfOperatingLeases" abstract="false" name="LesseeNumberOfOperatingLeases" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="sgp_LesseeOperatingLeaseNonCancellableLeasePeriod" abstract="false" name="LesseeOperatingLeaseNonCancellableLeasePeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="sgp_OperatingLeaseRentExpense" abstract="false" name="OperatingLeaseRentExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sgp_ShortTermLeaseAndVariableLeaseCost" abstract="false" name="ShortTermLeaseAndVariableLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
