In XSD do you have to import the standard schema in order to use it?

Question

I am trying to consume a SOAP API and I tackled this schema

While this schema doesn't explicitly imports any schema it uses the standard schema. i.e here

<xs:complexType name="AttributedQNameType" mixed="false">
    <xs:simpleContent>
        <xs:extension base="xs:QName">
            <xs:anyAttribute namespace="##other" processContents="lax"/>
        </xs:extension>
    </xs:simpleContent>
</xs:complexType>