Namespace error in <state> tag

The following example shows a <state> tag that does not contain a namespace.

<?xml version="1.0" encoding="UTF-8"?>
<rpc message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<get>
    <filter>
        <state>
        </state>
    </filter>
</get>
</rpc>
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The following example shows the reply, which returns errors.

<?xml version="1.0" encoding="UTF-8"?>
<rpc-reply message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
    <rpc-error>
        <error-type>protocol</error-type>
        <error-tag>bad-element</error-tag>
        <error-severity>error</error-severity>
        <error-message>
            Element is not valid in the specified context.
        </error-message>
        <error-info>
            <bad-element>state</bad-element>
        </error-info>
    </rpc-error>
</rpc-reply>
]]>]]>