This error i am getting from cloud server not in local machine 
This is the error log---------------------------

Traceback (most recent call last):
  File "/opt/odoo/odoo/odoo/http.py", line 640, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "/opt/odoo/odoo/odoo/http.py", line 677, in dispatch
    result = self._call_function(**self.params)
  File "/opt/odoo/odoo/odoo/http.py", line 333, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/opt/odoo/odoo/odoo/service/model.py", line 101, in wrapper
    return f(dbname, *args, **kwargs)
  File "/opt/odoo/odoo/odoo/http.py", line 326, in checked_call
    result = self.endpoint(*a, **kw)
  File "/opt/odoo/odoo/odoo/http.py", line 935, in __call__
    return self.method(*args, **kw)
  File "/opt/odoo/odoo/odoo/http.py", line 506, in response_wrap
    response = f(*args, **kw)
  File "/opt/odoo/odoo/addons/web/controllers/main.py", line 885, in call_kw
    return self._call_kw(model, method, args, kwargs)
  File "/opt/odoo/odoo/addons/web/controllers/main.py", line 877, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "/opt/odoo/odoo/odoo/api.py", line 687, in call_kw
    return call_kw_model(method, model, args, kwargs)
  File "/opt/odoo/odoo/odoo/api.py", line 672, in call_kw_model
    result = method(recs, *args, **kwargs)
  File "/opt/odoo/odoo/odoo/models.py", line 1932, in read_group
    result = self._read_group_raw(domain, fields, groupby, offset=offset, limit=limit, orderby=orderby, lazy=lazy)
  File "/opt/odoo/odoo/odoo/models.py", line 2036, in _read_group_raw
    data = map(lambda r: {k: self._read_group_prepare_data(k,v, groupby_dict) for k,v in r.iteritems()}, fetched_data)
  File "/opt/odoo/odoo/odoo/models.py", line 2036, in <lambda>
    data = map(lambda r: {k: self._read_group_prepare_data(k,v, groupby_dict) for k,v in r.iteritems()}, fetched_data)
  File "/opt/odoo/odoo/odoo/models.py", line 2036, in <dictcomp>
    data = map(lambda r: {k: self._read_group_prepare_data(k,v, groupby_dict) for k,v in r.iteritems()}, fetched_data)
  File "/opt/odoo/odoo/odoo/models.py", line 1831, in _read_group_prepare_data
    value = pytz.timezone(self._context['tz']).localize(value)
  File "/usr/lib/python2.7/dist-packages/pytz/tzinfo.py", line 304, in localize
    raise ValueError('Not naive datetime (tzinfo is already set)')
ValueError: Not naive datetime (tzinfo is already set)