code: func (c *c14N10ExclusiveCanonicalizer) Canonicalize(el *etree.Element) ([]byte, error) {
  	err := etreeutils.TransformExcC14n(el, c.prefixList)
  	if err != nil {
  		return nil, err
  	}
  
  	return canonicalSerialize(el)
  }
docs: // Canonicalize transforms the input Element into a serialized XML document in canonical form.