PEP 814: Fix typos (#4708)

Author: vstinner

peps/pep-0814.rst

@@ -80,8 +80,8 @@ Construction
 * ``frozendict(collection, **kwargs)`` combines the two previous
   constructions.
 
-Keys must be hashable and so immutable, but values can be mutable.
-Using immutable values creates a hashtable ``frozendict``.
+Keys must be hashable and therefore immutable, but values can be mutable.
+Using immutable values creates a hashable ``frozendict``.
 
 Creating a ``frozendict`` from a ``dict``, ``frozendict(dict)``, has a
 complexity of *O*\ (*n*): items are copied (shallow copy).
@@ -164,7 +164,7 @@ See also :pep:`584` "Add Union Operators To dict".
 Copy
 ----
 
-``frozencopy.copy()`` returns a shallow copy. In CPython, it simply
+``frozendict.copy()`` returns a shallow copy. In CPython, it simply
 returns the same ``frozendict`` (new reference).
 
 Use ``copy.deepcopy()`` to get a deep copy.