what the reason for this error please 

RPC_ERROR

Odoo Server Error

Traceback (most recent call last):

File "/opt/odoo/odoo/addons/base/models/ir_http.py", line 237, in _dispatch

result = request.dispatch()

File "/opt/odoo/odoo/http.py", line 688, in dispatch

result = self._call_function(**self.params)

File "/opt/odoo/odoo/http.py", line 360, in _call_function

return checked_call(self.db, *args, **kwargs)

File "/opt/odoo/odoo/service/model.py", line 94, in wrapper

return f(dbname, *args, **kwargs)

File "/opt/odoo/odoo/http.py", line 349, in checked_call

result = self.endpoint(*a, **kw)

File "/opt/odoo/odoo/http.py", line 917, in __call__

return self.method(*args, **kw)

File "/opt/odoo/odoo/http.py", line 536, in response_wrap

response = f(*args, **kw)

File "/opt/odoo/addons/web/controllers/main.py", line 1352, in call_button

action = self._call_kw(model, method, args, kwargs)

File "/opt/odoo/addons/web/controllers/main.py", line 1340, in _call_kw

return call_kw(request.env[model], method, args, kwargs)

File "/opt/odoo/odoo/api.py", line 460, in call_kw

result = _call_kw_model(method, model, args, kwargs)

File "/opt/odoo/odoo/api.py", line 433, in _call_kw_model

result = method(recs, *args, **kwargs)

File "/opt/odoo/odoo/addons/base/models/ir_translation.py", line 744, in translate_fields

assert fld.translate and rec._name == fld.model_name

Exception



The above exception was the direct cause of the following exception:



Traceback (most recent call last):

File "/opt/odoo/odoo/http.py", line 644, in _handle_exception

return super(JsonRequest, self)._handle_exception(exception)

File "/opt/odoo/odoo/http.py", line 302, in _handle_exception

raise exception.with_traceback(None) from new_cause

AssertionError