Python encode decode utf8 hex unicode

#!/usr/bin/python2.7

def hexdecode(value):
    """
    Decodes string value from hex to plain format

    >>> hexdecode('666f6f626172')
    'foobar'
    """

    value = value.lower()
    return (value[2:] if value.startswith("0x") else value).decode("hex")

def hexencode(value):
    """
    Encodes string value from plain to hex format

    >>> hexencode('foobar')
    '666f6f626172'
    """

    return utf8encode(value).encode("hex")

def unicodeencode(value, encoding=None):
    """
    Returns 8-bit string representation of the supplied unicode value

    >>> unicodeencode(u'foobar')
    'foobar'
    """

    retVal = value
    if isinstance(value, unicode):
        try:
            retVal = value.encode(encoding or UNICODE_ENCODING)
        except UnicodeEncodeError:
            retVal = value.encode(UNICODE_ENCODING, "replace")
    return retVal

def utf8encode(value):
    """
    Returns 8-bit string representation of the supplied UTF-8 value

    >>> utf8encode(u'foobar')
    'foobar'
    """

    return unicodeencode(value, "utf-8")

def utf8decode(value):
    """
    Returns UTF-8 representation of the supplied 8-bit string representation

    >>> utf8decode('foobar')
    u'foobar'
    """

    return value.decode("utf-8")