unit testing - Nosetests assert_equal apparently not equal to python == -

i'm programming temperature control setup has different sources (in example one):

source = source()  sources_dict = {     key: source }  temp_control = tempcontrol(args) #a dictionary built on instantiation based on args                                  #and assigned temp_control.sources 

sources_dict defined same args of tempcontrol(args). see content of loop works , not.

for key, value in tempcontrol.sources.iteritems():     assert_equal(value, sources_dict[key]) #fails     tempcontrol.sources[key] == sources_dict[key] #works     value == sources_dict[key] #works 

when not, following error message:

assertionerror: <pvd_temp_control.source object @ 0x02aa63b0> !=   <pvd_temp_cont rol.source object @ 0x02aa6330> -------------------- >> begin captured stdout << --------------------- sources_dict: {'cu': <pvd_temp_control.source object @ 0x02aa6330>} tempcontrol.sources: {'cu': <pvd_temp_control.source object @ 0x02aa63b0>} source: <pvd_temp_control.source object @ 0x02aa6330> --------------------- >> end captured stdout << ---------------------- 

any ideas why?

i had more specific. assert_equal won't magic , go through dictionary. correct example:

for key, value in tempcontrol.sources.iteritems():     assert_equal(value.element_name, sources_dict[key].key_name)