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    <link:label id="lab_eto_DocumentandEntityInformationAbstract_b3edb116-3097-4d64-be4f-f1828c0fe38e_terseLabel_en-US" xlink:label="lab_eto_DocumentandEntityInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
    <link:label id="lab_eto_DocumentandEntityInformationAbstract_label_en-US" xlink:label="lab_eto_DocumentandEntityInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
    <link:label id="lab_eto_DocumentandEntityInformationAbstract_documentation_en-US" xlink:label="lab_eto_DocumentandEntityInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
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    <link:label id="lab_dei_EntityAddressPostalZipCode_d1968bad-7d75-4baa-b28b-c6b00f05e46f_terseLabel_en-US" xlink:label="lab_dei_EntityAddressPostalZipCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
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    <link:label id="lab_dei_Security12bTitle_c7def808-a5cb-4548-94e7-46b97428dd18_terseLabel_en-US" xlink:label="lab_dei_Security12bTitle" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Title of 12(b) Security</link:label>
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    <link:label id="lab_us-gaap_DebtInstrumentAxis_38198a77-5f55-4d10-a88d-f076cf896fcc_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument [Axis]</link:label>
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    <link:label id="lab_dei_EntityAddressCityOrTown_ce18bdd5-3051-4f87-bfe0-a58638700d17_terseLabel_en-US" xlink:label="lab_dei_EntityAddressCityOrTown" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, City or Town</link:label>
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    <link:label id="lab_dei_EntityAddressAddressLine1_0940fb2d-7cd2-4f7c-940d-3d8546fb6d29_terseLabel_en-US" xlink:label="lab_dei_EntityAddressAddressLine1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, Address Line One</link:label>
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