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  <xs:element id="fsbc_NumberOfBranchOffices" abstract="false" name="NumberOfBranchOffices" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsbc_DebtInstrumentFloatingInterestRate" abstract="false" name="DebtInstrumentFloatingInterestRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsbc_FinancingReceivables30To89DaysPastDueMember" abstract="false" name="FinancingReceivables30To89DaysPastDueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_FederalReserveBankOfSanFranciscoMember" abstract="true" name="FederalReserveBankOfSanFranciscoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_AgriculturalLinesOfCreditMember" abstract="false" name="AgriculturalLinesOfCreditMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_NumberOfCorrespondentBanks" abstract="false" name="NumberOfCorrespondentBanks" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsbc_ScheduleOfProFormaEarningPerShareTableTextBlock" abstract="false" name="ScheduleOfProFormaEarningPerShareTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="fsbc_RealEstateRelatedLoansPercentage" abstract="false" name="RealEstateRelatedLoansPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsbc_CDARSMember" abstract="false" name="CDARSMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_InterestExpenseDomesticDepositLiabilitiesTimeDeposit250000Minimum" abstract="false" name="InterestExpenseDomesticDepositLiabilitiesTimeDeposit250000Minimum" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_ScheduleOfActivityInTheAllowanceForLoanLossesTableTextBlock" abstract="false" name="ScheduleOfActivityInTheAllowanceForLoanLossesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="fsbc_LoanRelatedExpenses" abstract="false" name="LoanRelatedExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerFairValue" abstract="false" name="DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_CommonStockConvertibleSharesIssuable" abstract="false" name="CommonStockConvertibleSharesIssuable" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="fsbc_PercentageOfLargestSingleDepositToDeposits" abstract="false" name="PercentageOfLargestSingleDepositToDeposits" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsbc_FederalHomeLoanBankStockAnnualizedDividendRatePercentage" abstract="false" name="FederalHomeLoanBankStockAnnualizedDividendRatePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsbc_ProFormaProvisionForIncomeTaxes" abstract="false" name="ProFormaProvisionForIncomeTaxes" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_UnvestedRestrictedShares" abstract="false" name="UnvestedRestrictedShares" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="fsbc_NumberOfShareholders" abstract="false" name="NumberOfShareholders" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsbc_ScheduleOfProFormaProvisionOfIncomeTaxesTableTextBlock" abstract="false" name="ScheduleOfProFormaProvisionOfIncomeTaxesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="fsbc_FixedToFloatingRateSubordinatedNotesIssuedSep2017Member" abstract="true" name="FixedToFloatingRateSubordinatedNotesIssuedSep2017Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_InterestBearingDepositsTable" abstract="true" name="InterestBearingDepositsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="fsbc_DebtSecuritiesHeldToMaturityContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" abstract="false" name="DebtSecuritiesHeldToMaturityContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsbc_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_UndisbursedConstructionLoansMember" abstract="false" name="UndisbursedConstructionLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_NumberOfUnsecuredFederalFunds" abstract="false" name="NumberOfUnsecuredFederalFunds" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsbc_ReclassificationAdjustmentForNetRealizedGainsIncludedInNetIncome" abstract="false" name="ReclassificationAdjustmentForNetRealizedGainsIncludedInNetIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_FinancialLiabilitiesRecordedAtAmortizedCostAbstract" abstract="true" name="FinancialLiabilitiesRecordedAtAmortizedCostAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fsbc_TimeDepositAtFairValueDisclosure" abstract="false" name="TimeDepositAtFairValueDisclosure" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_UndisbursedCommercialRealEstateLoansMember" abstract="false" name="UndisbursedCommercialRealEstateLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_ResidentialConstructionLoansMember" abstract="false" name="ResidentialConstructionLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsbc_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValue" abstract="false" name="DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsbc_InterestBearingDepositsTextBlock" abstract="false" name="InterestBearingDepositsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="fsbc_NumberOfUnsecuredFederalFundsIncreased" abstract="false" name="NumberOfUnsecuredFederalFundsIncreased" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsbc_LesseeOperatingLeaseLiabilityToBePaidDiscountForPresentValue" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidDiscountForPresentValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
