ne; this is the
        client side filename, *not* the file name on which it is
        stored (that's a temporary file you don't deal with)

    value: the value as a *string*; for file uploads, this
        transparently reads the file every time you request the value
        and returns *bytes*

    file: the file(-like) object from which you can read the data *as
        bytes* ; None if the data is stored a simple string

    type: the content-type, or None if not specified

    type_options: dictionary of options specified on the content-type
        line

    disposition: content-disposition, or None if not specified

    disposition_options: dictionary of corresponding options

    headers: a dictionary(-like) object (sometimes email.message.Message or a
        subclass thereof) containing *all* headers

    The class is subclassable, mostly for the purpose of overriding
    the make_file() method, which is called internally to come up with
    a file open for reading and writing.  This makes it possible to
    override the default choice of storing all files in a temporary
    directory and unlinking them as soon as they have been opened.

    N