def safe_identifier(name: str) -> str:
    """Make a string safe to be used as Python identifier.
    >>> safe_identifier("12abc")
    '_12abc'
    >>> safe_identifier("__editable__.myns.pkg-78.9.3_local")
    '__editable___myns_pkg_78_9_3_local'
    """
    safe = re.sub(r'\W|^(?=\d)', '_', name)
    assert safe.isidentifier()
    return safe
Make a string safe to be used as Python identifier.
    >>> safe_identifier("12abc")
    '_12abc'
    >>> safe_identifier("__editable__.myns.pkg-78.9.3_local")
    '__editable___myns_pkg_78_9_3_local'
    
product/gradle-plugin/src/main/python/setuptools/_normalization.py