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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def maybe_inspect_zip(models):
    r'''
    Detect if models is a list of protocolbuffer files or a ZIP file.
    If the latter, then unzip it and return the list of protocolbuffer files
    that were inside.
    '''

    if not(is_zip_file(models)):
        return models

    if len(models) > 1:
        return models

    if len(models) < 1:
        raise AssertionError('No models at all')

    return zipfile.ZipFile(models[0]).namelist()