Werkzeug Internal Server Error

traceback.txt

Traceback (most recent call last):
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1820, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1403, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1817, in wsgi_app
    response = self.full_dispatch_request()
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1477, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1381, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1475, in full_dispatch_request
    rv = self.dispatch_request()
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask/app.py", line 1461, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask_admin/base.py", line 68, in inner
    return self._run_view(f, *args, **kwargs)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask_admin/base.py", line 367, in _run_view
    return fn(self, *args, **kwargs)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask_admin/model/base.py", line 1834, in create_view
    model = self.create_model(form)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask_admin/contrib/peewee/view.py", line 430, in create_model
    if not self.handle_view_exception(ex):
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/flask_admin/contrib/peewee/view.py", line 425, in create_model
    model.save()
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/playhouse/signals.py", line 68, in save
    pre_save.send(self, created=created)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/playhouse/signals.py", line 40, in send
    responses.append((r, r(sender, instance, *args, **kwargs)))
  File "/home/tuk/Desktop/pyprojects/bulksms/app.py", line 104, in on_bulk_message_save_handler
    instance.file_fields = request.get_array(field_name='file')
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel_webio/__init__.py", line 78, in get_array
    return pe.get_array(**params)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel/__init__.py", line 78, in get_array
    sheet = get_sheet(**keywords)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel/sources/__init__.py", line 82, in get_sheet
    named_content = _get_content(**keywords)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel/sources/__init__.py", line 37, in _get_content
    sheet_name, data = source.get_data()
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel/sources/memory.py", line 44, in get_data
    **self.keywords)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel_io/__init__.py", line 161, in load_data
    **keywords)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel_xls/__init__.py", line 117, in __init__
    sheetname=sheetname, **keywords)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel_io/base.py", line 138, in __init__
    self.native_book = self.load_from_memory(file_content, **keywords)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/pyexcel_xls/__init__.py", line 144, in load_from_memory
    on_demand=on_demand)
  File "/home/tuk/.virtualenvs/bulksms/lib/python3.4/site-packages/xlrd/__init__.py", line 394, in open_workbook
    f = open(filename, "rb")
TypeError: invalid file: None