Determine if data type is committed
output = H5T.committed(type_id)
output = H5T.committed(type_id) returns
a positive value to indicate that the data type has been committed,
and zero to indicate that it has not. A negative value indicates failure.
type_id = H5T.copy('H5T_NATIVE_DOUBLE');
is_committed = H5T.committed(type_id);