<template id="template_logo_replaced" inherit_id="website.option_header_brand_logo">
<xpath expr="//a/span" position="replace">
<span t-field="website.logo" t-options="{'widget': 'image', 'width': 95, 'height': 40}" role="img" t-att-aria-label="'Logo of %s' % website.name" t-att-title="website.name"/>
</xpath>
</template>
it works