ZCML File
meta.zcml

<configure
    xmlns="http://namespaces.zope.org/zope"
    xmlns:meta="http://namespaces.zope.org/meta"
    >
<meta:directive
    namespace="http://namespaces.zope.org/apidoc"
    name="bookchapter"
    schema=".metadirectives.IBookChapterDirective"
    handler=".metaconfigure.bookchapter"
    />
</configure>