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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 get_install_requires_odoo_addons(addons_dir, depends_override={}, external_dependencies_override={}, odoo_version_override=None):
 """ Get the list of requirements for a directory containing addons """

    addon_dirs = []
    addons = os.listdir(addons_dir)
    for addon in addons:
        addon_dir = os.path.join(addons_dir, addon)
        if is_installable_addon(addon_dir):
            addon_dirs.append(addon_dir)
    install_requires = set()
    for addon_dir in addon_dirs:
        r = get_install_requires_odoo_addon(
            addon_dir,
            no_depends=addons,
            depends_override=depends_override,
            external_dependencies_override=external_dependencies_override,
            odoo_version_override=odoo_version_override,
        )
        install_requires.update(r)
    return sorted(install_requires)