(value)
return token, value
word = atom / quoted-string

    Either atom or quoted-string may start with CFWS.  We have to peel off this
    CFWS first to determine which type of word to parse.  Afterward we splice
    the leading CFWS, if any, into the parsed sub-token.

    If neither an atom or a quoted-string is found before the next special, a
    HeaderParseError is raised.

    The token returned is either an Atom or a QuotedString, as appropriate.
    This means the 'word' level of the formal grammar is not represented in the
    parse tree; this is because having that extra layer when manipulating the
    parse tree is more confusing than it is helpful.
word = atom / quoted-string
word = atom / quoted - string
def get_word(value):
    """word = atom / quoted-string

    Either atom or quoted-string may start with CFWS.  We have to peel off this
    CFWS first to determine which type of word to parse.  Afterward we splice
    the leading CFWS, if any, into the parsed sub-token.

    If neither an atom or a quoted-string is found before the next special, a
    HeaderParseError is raised.

    The token returned is either an Atom or a QuotedString, as appropriate.
    This means the 'word' level of the formal grammar is not represented in the
    parse tree; this is because having that extra layer when manipulating the
    parse tree is more confusing than it is helpful.

    """
    if value[0] in CFWS_LEADER:
        leader, value = get_cfws(value)
    else:
        leader = None
    if not value:
        raise errors.HeaderParseError(
            "Expected 'atom' or 'quoted-string' but found nothing.")
    if value[0]=='"':
        token, value = get_quoted_string(value)
    elif value[0] in SPECIALS:
        raise errors.HeaderParseError("Expected 'atom' or 'quoted-string' "
                                      "but found '{}'".format(value))
    else:
        token, value = get_atom(value)
    if leader is not None:
        token[:0] = [leader]
    return token, value
def get_word ( value ) : if value [ 0 ] in CFWS_LEADER : leader , value = get_cfws ( value ) else : leader = None if not value : raise errors . HeaderParseError ( "Expected 'atom' or 'quoted-string' but found nothing." ) if value [ 0 ] == '"' : token , value = get_quoted_string ( value ) elif value [ 0 ] in SPECIALS : raise errors . HeaderParseError ( "Expected 'atom' or 'quoted-string' " "but found '{}'" . format ( value ) ) else : token , value = get_atom ( value ) if leader is not None : token [ : 0 ] = [ leader ] return token , value