ModuleNotFound error.

[hammer]

I created a new environment (env2) and used pip to install KivyCalendar-indicates installed successfully,see below. The application and its associated data base is located in this same environment folder. There has only been python 3.8 installed on this machine.

Where should i start looking to understand why it can not find it?

(env2) mark@mark-Latitude-E7240:~/env2$ pip install KivyCalendar
Processing /home/mark/.cache/pip/wheels/12/fe/f3/4c752c69dcefda3d061a8318880e1a36c11f7e2170673eed4e/KivyCalendar-0.1.3-py3-none-any.whl
Collecting kivy
  Using cached Kivy-2.0.0-cp38-cp38-manylinux2010_x86_64.whl (22.2 MB)
Collecting docutils
  Downloading docutils-0.18.1-py2.py3-none-any.whl (570 kB)
     |████████████████████████████████| 570 kB 514 kB/s 
Processing /home/mark/.cache/pip/wheels/d2/72/1a/9ddd17f00755707937caa350616965fb3330a6270425f397e6/Kivy_Garden-0.1.4-py3-none-any.whl
Collecting pygments
  Downloading Pygments-2.11.2-py3-none-any.whl (1.1 MB)
     |████████████████████████████████| 1.1 MB 1.4 MB/s 
Collecting requests
  Downloading requests-2.27.1-py2.py3-none-any.whl (63 kB)
     |████████████████████████████████| 63 kB 686 kB/s 
Collecting urllib3<1.27,>=1.21.1
  Downloading urllib3-1.26.8-py2.py3-none-any.whl (138 kB)
     |████████████████████████████████| 138 kB 2.1 MB/s 
Collecting certifi>=2017.4.17
  Using cached certifi-2021.10.8-py2.py3-none-any.whl (149 kB)
Collecting idna<4,>=2.5; python_version >= "3"
  Using cached idna-3.3-py3-none-any.whl (61 kB)
Collecting charset-normalizer~=2.0.0; python_version >= "3"
  Downloading charset_normalizer-2.0.12-py3-none-any.whl (39 kB)
Installing collected packages: docutils, urllib3, certifi, idna, charset-normalizer, requests, Kivy-Garden, pygments, kivy, KivyCalendar
Successfully installed Kivy-Garden-0.1.4 KivyCalendar-0.1.3 certifi-2021.10.8 charset-normalizer-2.0.12 docutils-0.18.1 idna-3.3 kivy-2.0.0 pygments-2.11.2 requests-2.27.1 urllib3-1.26.8
(env2) mark@mark-Latitude-E7240:~/env2$ 


Exception has occurred: ModuleNotFoundError
No module named 'calendar_ui'
  File "/home/mark/env2/Bovine25.py", line 39, in <module>
    from KivyCalendar import CalendarWidget