LookupError: unknown encoding when character_set_client is utf8mb4

[Brian Panulla]

When setting MySQL character_set_client to "utf8mb4" to support reading the full range of emojiis oursql throws a lookup error:

Traceback (most recent call last):
  File "test_utf8mb4.py", line 20, in <module>
    results = cursor.fetchone()
  File "oursqlx/cursor.pyx", line 185, in oursql.Cursor.fetchone (oursqlx/oursql.c:21389)
  File "oursqlx/util.pyx", line 47, in oursql._DictWhateverMixin.fetchone (oursqlx/oursql.c:3863)
  File "oursqlx/statement.pyx", line 496, in oursql._Statement.fetchone (oursqlx/oursql.c:14095)
LookupError: unknown encoding: utf8mb4

This error doesn't occur when setting character set to "utf8" or "latin1".

Python 2.7.11
oursql 0.9.3.1, 0.9.3.2
MySQL client/server 5.6.24-72.2
Mac OS X 10.10.5

Test script attached using the MySQL test database. No tables required.