Test importer interface

[FilippoULIVO]

in relation to issue #1158 this is my first time contributing to this project so let me know for any defects, I'm happy to take any critic.

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[FilippoULIVO]

@jzacsh I managed to open a pull request thanks to your help 😄 the forced push come from amend to the author(since it was my employer's email). Would you please review?

[CLAassistant]

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