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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 find_encodings(enc=None, system=False):
 """Find functions for encoding translations for a specific codec. :param str enc: The codec to find translation functions for. It will be normalized by converting to lowercase, excluding everything which is not ascii, and hyphens will be converted to underscores. :param bool system: If True, find encodings based on the system's stdin encoding, otherwise assume utf-8. :raises: :exc:LookupError if the normalized codec, ``enc``, cannot be found in Python's encoding translation map. """

    if not enc:
        enc = 'utf-8'

    if system:
        if getattr(sys.stdin, 'encoding', None) is None:
            enc = sys.stdin.encoding
            log.debug("Obtained encoding from stdin: %s" % enc)
        else:
            enc = 'ascii'

    ## have to have lowercase to work, see
    ## http://docs.python.org/dev/library/codecs.html#standard-encodings
    enc = enc.lower()
    codec_alias = encodings.normalize_encoding(enc)

    codecs.register(encodings.search_function)
    coder = codecs.lookup(codec_alias)

    return coder