Previously, the MySQL-Python DBAPI was observed under some circumstances using the ProgrammingError exception class to report on the 'command out of sync' errors, which is considered to be the case where a connection need to be thrown away; the SQLAlchemy dialect only expected this error to be emitted within the OperationalError class. As a result, in some cases a MySQL-Python connection that became corrupt would not signal to the SQLAlchemy engine that the pool of connections should be disposed, leading the engine not being able to proceed with new operations. With this update, the error handling scheme of the MySQL-Python dialect is modified to expect either the OperationalError or ProgrammingError exception class when testing for this particular class of error. As a result, the SQLAlchemy engine/connection pool now correctly disposes off its connections when a MySQL-Python ProgrammingError delivers the 'command out of sync' error code.