Additionnal installation to handle 'ImportError: Unable to import required dependencies:'

[LD40]

When trying to install PyGazpar independantly from HomeAssistant package, to use it on a Domoticz installation on a raspberry, I encounteredthe following error when trying to use it:

  File "/home/pi/domoticz/plugins/pyGazpar/gazpar.py", line 5, in <module>
    import pygazpar
  File "/usr/local/lib/python3.9/dist-packages/pygazpar/__init__.py", line 2, in <module>
    from pygazpar.client import Client  # noqa: F401
  File "/usr/local/lib/python3.9/dist-packages/pygazpar/client.py", line 4, in <module>
    from pygazpar.datasource import IDataSource, MeterReadingsByFrequency
  File "/usr/local/lib/python3.9/dist-packages/pygazpar/datasource.py", line 6, in <module>
    import pandas as pd
  File "/usr/local/lib/python3.9/dist-packages/pandas/__init__.py", line 19, in <module>
    raise ImportError(
ImportError: Unable to import required dependencies:
numpy: Error importing numpy: you should not try to import numpy from
        its source directory; please exit the numpy source tree, and relaunch
        your python interpreter from there.

Just to let you know that the issue was solved simply with:
sudo apt-get install libopenblas-dev

(Solution found on: stackoverflow)