The DOMImplementation interface provides a way for
applications to determine the availability of particular features in
the DOM they are using. DOM Level 2 added the ability to create new
Document and DocumentType objects using the
DOMImplementation as well.
Return true if the feature identified by the pair of strings
feature and version is implemented.
namespaceUri, qualifiedName, doctype)
Return a new Document object (the root of the DOM), with a
child Element object having the given namespaceUri and
qualifiedName. The doctype must be a DocumentType
object created by createDocumentType(), or None.
In the Python DOM API, the first two arguments can also be None
in order to indicate that no Element child is to be created.
qualifiedName, publicId, systemId)
Return a new DocumentType object that encapsulates the given
qualifiedName, publicId, and systemId strings,
representing the information contained in an XML document type