Starting from version 2.0.0 python2 is no longer supported the 1.x series will remain supported but no new features will be added.
f = Mock() f.method('foo', 'bar') assert_that(f.method, called_once_with(anything(), 'bar')
called- match mock that was called one or more times
not_called- match mock that was never called
called_once- match mock that was called once regardless of arguments
called_with- match mock has at least one call with the specified arguments
called_once_with- match mock that was called once and with the specified arguments
called_n_times- match mock that was called number of times.