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13.6.2.6 Element Objects

`Element` is a subclass of `Node`, so inherits all the attributes of that class.

`tagName`
  The element type name. In a namespace-using document it may have colons in it. The value is a string.

`getElementsByTagName`(tagName)
  Same as equivalent method in the `Document` class.

`getElementsByTagNameNS`(tagName)
  Same as equivalent method in the `Document` class.

`getAttribute`(attname)
  Return an attribute value as a string.

`getAttributeNode`(attrname)
  Return the `Attr` node for the attribute named by attrname.

`getAttributeNS`(namespaceURI, localName)
  Return an attribute value as a string, given a namespaceURI and localName.

`getAttributeNodeNS`(namespaceURI, localName)
  Return an attribute value as a node, given a namespaceURI and localName.

`removeAttribute`(attname)
  Remove an attribute by name. No exception is raised if there is no matching attribute.

`removeAttributeNode`(oldAttr)
  Remove and return oldAttr from the attribute list, if present. If oldAttr is not present, `NotFoundErr` is raised.

`removeAttributeNS`(namespaceURI, localName)
  Remove an attribute by name. Note that it uses a localName, not a qname. No exception is raised if there is no matching attribute.

`setAttribute`(attname, value)
  Set an attribute value from a string.

`setAttributeNode`(newAttr)
  Add a new attibute node to the element, replacing an existing attribute if necessary if the `name` attribute matches. If a replacement occurs, the old attribute node will be returned. If newAttr is already in use, `InuseAttributeErr` will be raised.

`setAttributeNodeNS`(newAttr)
  Add a new attibute node to the element, replacing an existing attribute if necessary if the `namespaceURI` and `localName` attributes match. If a replacement occurs, the old attribute node will be returned. If newAttr is already in use, `InuseAttributeErr` will be raised.

`setAttributeNS`(namespaceURI, qname, value)
  Set an attribute value from a string, given a namespaceURI and a qname. Note that a qname is the whole attribute name. This is different than above.