i get this error just if i start the service odoo from the file if i start the service odoo from terminal it's work normal 
Traceback (most recent call last):
  File "/home/amine/odoo/15.0/odoo/odoo/addons/base/models/ir_http.py", line 237, in _dispatch
    result = request.dispatch()
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 687, in dispatch
    result = self._call_function(**self.params)
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 359, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/home/amine/odoo/15.0/odoo/odoo/service/model.py", line 94, in wrapper
    return f(dbname, *args, **kwargs)
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 348, in checked_call
    result = self.endpoint(*a, **kw)
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 916, in __call__
    return self.method(*args, **kw)
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 535, in response_wrap
    response = f(*args, **kw)
  File "/home/amine/odoo/15.0/odoo/addons/web/controllers/main.py", line 1346, in call_button
    action = self._call_kw(model, method, args, kwargs)
  File "/home/amine/odoo/15.0/odoo/addons/web/controllers/main.py", line 1334, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "/home/amine/odoo/15.0/odoo/odoo/api.py", line 464, in call_kw
    result = _call_kw_multi(method, model, args, kwargs)
  File "/home/amine/odoo/15.0/odoo/odoo/api.py", line 451, in _call_kw_multi
    result = method(recs, *args, **kwargs)
  File "/home/amine/odoo/15.0/custom/uma/models/statistique_statistique.py", line 179, in dossier_statistique
    writer = pd.ExcelWriter('statistique.xlsx', engine='openpyxl')
  File "/home/amine/.local/lib/python3.8/site-packages/pandas/io/excel/_openpyxl.py", line 60, in __init__
    super().__init__(
  File "/home/amine/.local/lib/python3.8/site-packages/pandas/io/excel/_base.py", line 1313, in __init__
    self._handles = get_handle(
  File "/home/amine/.local/lib/python3.8/site-packages/pandas/io/common.py", line 865, in get_handle
    handle = open(handle, ioargs.mode)
Exception

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

Traceback (most recent call last):
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 643, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "/home/amine/odoo/15.0/odoo/odoo/http.py", line 301, in _handle_exception
    raise exception.with_traceback(None) from new_cause
PermissionError: [Errno 13] Permission denied: 'statistique.xlsx'