@@ -580,10 +580,9 @@ Functions
 .. function:: Comment(text=None)
 
    Comment element factory.  This factory function creates a special element
-   that will be serialized as an XML comment by the standard serializer.  The
-   comment string can be either a bytestring or a Unicode string.  *text* is a
-   string containing the comment string.  Returns an element instance
-   representing a comment.
+   that will be serialized as an XML comment by the standard serializer.
+   *text* is a string containing the comment string.
+   Returns an element instance representing a comment.
 
    Note that :class:`XMLParser` skips over comments in the input
    instead of creating comment objects for them. An :class:`ElementTree` will
@@ -650,10 +649,11 @@ Functions
    ``"pi"``, ``"start-ns"`` and ``"end-ns"``
    (the "ns" events are used to get detailed namespace
    information).  If *events* is omitted, only ``"end"`` events are reported.
-   *parser* is an optional parser instance.  If not given, the standard
-   :class:`XMLParser` parser is used.  *parser* must be a subclass of
-   :class:`XMLParser` and can only use the default :class:`TreeBuilder` as a
-   target. Returns an :term:`iterator` providing ``(event, elem)`` pairs;
+   *parser* is an optional parser instance.
+   If not given, the standard :class:`XMLParser` parser is used.
+   *parser* must be an instance of :class:`XMLParser` or its subclass
+   and can only use the default :class:`TreeBuilder` as a target.
+   Returns an :term:`iterator` providing ``(event, elem)`` pairs;
    it has a ``root`` attribute that references the root element of the
    resulting XML tree once *source* is fully read.
    The iterator has the :meth:`!close` method that closes the internal
@@ -729,8 +729,7 @@ Functions
    Subelement factory.  This function creates an element instance, and appends
    it to an existing element.
 
-   The element name, attribute names, and attribute values can be either
-   bytestrings or Unicode strings.  *parent* is the parent element.  *tag* is
+   *parent* is the parent element.  *tag* is
    the subelement name.  *attrib* is an optional dictionary, containing element
    attributes.  *extra* contains additional attributes, given as keyword
    arguments.  Returns an element instance.
@@ -921,11 +920,22 @@ Element Objects
    Element class.  This class defines the Element interface, and provides a
    reference implementation of this interface.
 
-   The element name, attribute names, and attribute values can be either
-   bytestrings or Unicode strings.  *tag* is the element name.  *attrib* is
+   *tag* is the element name.  *attrib* is
    an optional dictionary, containing element attributes.  *extra* contains
    additional attributes, given as keyword arguments.
 
+   The element name and the attribute names and values are strings or
+   :class:`QName` instances, and the text and the tail are strings or
+   ``None``.
+   The element name can also be :func:`Comment` or
+   :func:`ProcessingInstruction`, which are used for special elements.
+   If it is ``None``, the element itself is not serialized: only its text
+   and its children are written, and its attributes are ignored.
+   This can be used for a fragment which contains several elements.
+   With ``method="html"`` the attribute value can also be ``None``,
+   which produces an empty attribute (such as ``checked``).
+   Other objects can be stored in the tree, but they cannot be serialized.
+
    .. versionchanged:: 3.15
       *attrib* can now be a :class:`frozendict`.
 
@@ -991,14 +1001,12 @@ Element Objects
 
    .. method:: items()
 
-      Returns the element attributes as a sequence of (name, value) pairs.  The
-      attributes are returned in an arbitrary order.
+      Returns the element attributes as (name, value) pairs.
 
 
    .. method:: keys()
 
-      Returns the elements attribute names as a list.  The names are returned
-      in an arbitrary order.
+      Returns the element attribute names.
 
 
    .. method:: set(key, value)
@@ -1329,8 +1337,7 @@ TreeBuilder Objects
 
    .. method:: data(data)
 
-      Adds text to the current element.  *data* is a string.  This should be
-      either a bytestring, or a Unicode string.
+      Adds text to the current element.  *data* is a string.
 
 
    .. method:: end(tag)
@@ -1433,7 +1440,8 @@ XMLParser Objects
 
    .. method:: feed(data)
 
-      Feeds data to the parser.  *data* is encoded data.
+      Feeds data to the parser.  *data* is a string
+      or encoded data (:class:`bytes` or a :term:`bytes-like object`).
 
 
    .. method:: flush()
@@ -1512,7 +1520,8 @@ XMLPullParser Objects
 
    .. method:: feed(data)
 
-      Feed the given bytes data to the parser.
+      Feed the given data to the parser.  *data* is a string
+      or encoded data (:class:`bytes` or a :term:`bytes-like object`).
 
    .. method:: flush()
 
 
@@ -129,9 +129,6 @@ class Element:
     want to check if an element is truly empty, you should check BOTH
     its length AND its text attribute.
 
-    The element tag, attribute names, and attribute values can be either
-    bytes or strings.
-
     *tag* is the element name.  *attrib* is an optional dictionary containing
     element attributes. *extra* are additional element attributes given as
     keyword arguments.
@@ -359,21 +356,17 @@ def set(self, key, value):
         self.attrib[key] = value
 
     def keys(self):
-        """Get list of attribute names.
+        """Get attribute names.
 
-        Names are returned in an arbitrary order, just like an ordinary
-        Python dict.  Equivalent to attrib.keys()
+        Equivalent to attrib.keys()
 
         """
         return self.attrib.keys()
 
     def items(self):
-        """Get element attributes as a sequence.
-
-        The attributes are returned in arbitrary order.  Equivalent to
-        attrib.items().
+        """Get element attributes as (name, value) pairs.
 
-        Return a list of (name, value) tuples.
+        Equivalent to attrib.items().
 
         """
         return self.attrib.items()