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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 to_slug(value, incoming=None, errors="strict"):
 """Normalize string. Convert to lowercase, remove non-word characters, and convert spaces to hyphens. This function was copied from novaclient.openstack.strutils Inspired by Django's `slugify` filter. :param value: Text to slugify :param incoming: Text's current encoding :param errors: Errors handling policy. See here for valid values http://docs.python.org/2/library/codecs.html :returns: slugified unicode representation of `value` :raises TypeError: If text is not an instance of str """

    value = safe_decode(value, incoming, errors)
    # NOTE(aababilov): no need to use safe_(encode|decode) here:
    # encodings are always "ascii", error handling is always "ignore"
    # and types are always known (first: unicode; second: str)
    value = unicodedata.normalize("NFKD", value).encode(
        "ascii", "ignore").decode("ascii")
    value = SLUGIFY_STRIP_RE.sub("", value).strip().lower()
    return SLUGIFY_HYPHENATE_RE.sub("-", value)