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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0000099780-06-000068.txt : 20060815
<SEC-HEADER>0000099780-06-000068.hdr.sgml : 20060815
<ACCEPTANCE-DATETIME>20060815145016
ACCESSION NUMBER:		0000099780-06-000068
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060814
FILED AS OF DATE:		20060815
DATE AS OF CHANGE:		20060815

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TRINITY INDUSTRIES INC
		CENTRAL INDEX KEY:			0000099780
		STANDARD INDUSTRIAL CLASSIFICATION:	RAILROAD EQUIPMENT [3743]
		IRS NUMBER:				750225040
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2525 STEMMONS FREEWAY
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75207-2401
		BUSINESS PHONE:		214-631-4420

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TRINITY STEEL CO INC
		DATE OF NAME CHANGE:	19720407

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WALLACE TIMOTHY R
		CENTRAL INDEX KEY:			0001195484

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06903
		FILM NUMBER:		061034796

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		214-631-4420

	MAIL ADDRESS:	
		STREET 1:		2525 STEMMONS FREEWAY
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75207
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-08-14</periodOfReport>

    <issuer>
        <issuerCik>0000099780</issuerCik>
        <issuerName>TRINITY INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>NYSE/TRN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001195484</rptOwnerCik>
            <rptOwnerName>WALLACE TIMOTHY R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2525 STEMMONS FREEWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75207</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman, President &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1765</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
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                    <value>57688</value>
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                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by 2525 Investment, LP a Limited Partnership</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2006-08-14</value>
            </transactionDate>
            <transactionCoding>
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                <transactionCode>M</transactionCode>
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            <transactionAmounts>
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                <transactionPricePerShare>
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            <ownershipNature>
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        <nonDerivativeTransaction>
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                <value>Common Stock</value>
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            <transactionDate>
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            <transactionAmounts>
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                </transactionShares>
                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            <ownershipNature>
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            <ownershipNature>
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        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
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            <transactionCoding>
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                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>46347</value>
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                <transactionPricePerShare>
                    <value>11.3333</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
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            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>943573</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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                <natureOfOwnership>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-08-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>20551</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18.94</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>964124</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-08-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>8850</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>17.94</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>972974</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-08-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>39345</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>33.53</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>933629</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
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            <transactionDate>
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            <transactionCoding>
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                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>20000</value>
                </transactionShares>
                <transactionPricePerShare>
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                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
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            </securityTitle>
            <conversionOrExercisePrice>
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                <footnoteId id="F6"/>
            </conversionOrExercisePrice>
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            <transactionAmounts>
                <transactionShares>
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                </transactionShares>
                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            </transactionAmounts>
            <exerciseDate>
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            </exerciseDate>
            <expirationDate>
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            </expirationDate>
            <underlyingSecurity>
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            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
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                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeHolding>
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                <footnoteId id="F7"/>
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            <expirationDate>
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            <underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
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        </derivativeHolding>
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        </derivativeHolding>
        <derivativeHolding>
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            <expirationDate>
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                </underlyingSecurityShares>
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                <sharesOwnedFollowingTransaction>
                    <value>22500</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
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        </derivativeHolding>
        <derivativeHolding>
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            <transactionDate>
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            <transactionAmounts>
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            </underlyingSecurity>
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            <ownershipNature>
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        </derivativeTransaction>
        <derivativeTransaction>
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            <conversionOrExercisePrice>
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            <transactionDate>
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                </transactionShares>
                <transactionPricePerShare>
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                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F1"/>
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            <expirationDate>
                <value>2014-05-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
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                    <footnoteId id="F11"/>
                </underlyingSecurityShares>
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                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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                <natureOfOwnership>
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                </natureOfOwnership>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
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            <conversionOrExercisePrice>
                <value>17.94</value>
                <footnoteId id="F12"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-08-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>8850</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
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            <expirationDate>
                <value>2009-10-29</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>44250</value>
                    <footnoteId id="F12"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>35400</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Option Term is Ten Years.  Options vest over 5 years at twenty percent (20%) per year beginning on the first anniversary of the grant date.</footnote>
        <footnote id="F2">Option Term is Ten Years.  Options vest over 4 years at twenty-five percent (25%) per year beginning on the first anniversary of the grant date.</footnote>
        <footnote id="F3">On May 26, 2006, the common stock of Trinity Industries, Inc. split 3-for-2, resulting in the reporting person's indirect ownership of 19,229 additional shares of common stock.</footnote>
        <footnote id="F4">On May 26, 2006, the common stock of Trinity Industries, Inc. split 3-for-2, resulting in the reporting person's indirect ownership of 45,531 additional shares of common stock.</footnote>
        <footnote id="F5">On May 26, 2006, the common stock of Trinity Industries, Inc. split 3-for-2, resulting in the reporting person's ownership of 296,134 additional shares of common stock.</footnote>
        <footnote id="F6">This option was previously reported as covering 25,695 shares at an exercise price of $25.11 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
        <footnote id="F7">This option was previously reported as covering 20,000 shares at an exercise price of $53.00 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
        <footnote id="F8">This option was previously reported as covering 15,000 shares at an exercise price of $39.3125 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
        <footnote id="F9">This option was previously reported as covering 38,500 shares at an exercise price of $39.3125 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
        <footnote id="F10">This option was previously reported as covering 110,340 shares at an exercise price of $17.00 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
        <footnote id="F11">This option was previously reported as covering 54,800 shares at an exercise price of $28.41 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
        <footnote id="F12">This option was previously reported as covering 29,500 shares at an exercise price of $26.91 per share, but was adjusted to reflect the stock split that occurred on May 26, 2006.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Michael G. Fortado  For:  Timothy R. Wallace</signatureName>
        <signatureDate>2006-08-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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