Simplify hy._compat.isidentifier

hy/_compat.py

@@ -18,27 +18,8 @@ def reraise(exc_type, value, traceback=None):
 
 
 def isidentifier(x):
-    if x in ('True', 'False', 'None', 'print'):
+    if x in ('True', 'False', 'None'):
-        # `print` is special-cased here because Python 2's
-        # keyword.iskeyword will count it as a keyword, but we
-        # use the __future__ feature print_function, which makes
-        # it a non-keyword.
         return True
     if keyword.iskeyword(x):
         return False
-    if PY3:
     return x.isidentifier()
-    if x.rstrip() != x:
-        return False
-    import tokenize as T
-    from io import StringIO
-    try:
-        tokens = list(T.generate_tokens(StringIO(x).readline))
-    except (T.TokenError, IndentationError):
-        return False
-    # Some versions of Python 2.7 (including one that made it into
-    # Ubuntu 18.10) have a Python 3 backport that adds a NEWLINE
-    # token. Remove it if it's present.
-    # https://bugs.python.org/issue33899
-    tokens = [t for t in tokens if t[0] != T.NEWLINE]
-    return len(tokens) == 2 and tokens[0][0] == T.NAME