Remove unused _has_unicode/_str_cls vars

Unused since 04f1c78c13.

memcache.py

@@ -78,17 +78,6 @@ def useOldServerHashFunction():
     serverHashFunction = binascii.crc32
 
 from io import BytesIO
-if six.PY2:
-    try:
-        unicode
-    except NameError:
-        _has_unicode = False
-    else:
-        _has_unicode = True
-else:
-    _has_unicode = True
-
-_str_cls = six.string_types
 
 valid_key_chars_re = re.compile(b'[\x21-\x7e\x80-\xff]+$')
 

tests/test_memcache.py

@@ -6,17 +6,6 @@ import six
 
 from memcache import Client, SERVER_MAX_KEY_LENGTH, SERVER_MAX_VALUE_LENGTH
 
-try:
-    _str_cls = basestring
-except NameError:
-    _str_cls = str
-
-
-def to_s(val):
-    if not isinstance(val, _str_cls):
-        return "%s (%s)" % (val, type(val))
-    return "%s" % val
-
 
 class FooStruct(object):