@staticmethod
def core_packages():
    """
        Return a list of core packages.

        List of packages that are core of the product. Most importantly,
        if they themselves define add-on/plugin entry points they must
        not be 'uninstalled' via a package manager, they can only be
        updated.

        Return
        ------
        packages : List[str]
            A list of package names (can also contain PEP-440 version
            specifiers).
        """
    return ['orange-canvas-core >= 0.0, < 0.1a']
