a file which does not exist.

    The correct way to use me is to instantiate me, and then do ALL filesystem
    access through me.  In other words, do not import the 'os' module; if you
    need to open a file, call my 'open' method.  If you need to list a
    directory, call my 'path' method.

    Even if you pass me a relative path, I will convert that to an absolute
    path internally.

    Note: although time-related methods do return floating-point results, they
    may still be only second resolution depending on the platform and the last
    value passed to L{os.stat_float_times}.  If you want greater-than-second
    precision, call C{os.stat_float_times(True)}, or use Python 2.5.
    Greater-than-second precision is only available in Windows on Python2.5 and
    later.

    The type of C{path} when instantiating decides the mode of the L{FilePath}.
    That is, C{FilePath(b"/")} will return a L{bytes} mode L{FilePath}, and
    C{FilePath(u"/")} will return a L{unicode} mode L{FilePath}.
    C{FilePath("/")} will return a L{bytes} mode L{FilePath} on Python 2, and a
    L{unicode} mode L{FilePath} on Python 3.

    Methods that return a new L{FilePath} use the type of the given subpath to
    decide its mode. For example, C{FilePath(b"/").child(u"tmp")} will return a
    L{unicode} mode L{FilePath}.

    @type alwaysCreate: L{bool}
    @ivar alwaysCreate: When opening this file, only succeed if the file does
        not already exist.

    @type path: L{bytes} or L{unicode}
    @ivar path: The path from which 'downward' traversal is permitted.

    @ivar statinfo: (WARNING: statinfo is deprecated as of Twisted 15.0.0 and
        will become a private attribute)
        The currently cached status information about the file on
        the filesystem that this L{FilePath} points to.  This attribute is
        L{None} if the file is in an indeterminate state (either this
        L{FilePath} has not yet had cause to call C{stat()} yet or
        L{FilePath.changed} indicated that new information is required), 0 if
        C{stat()} was called and returned an error (i.e. the path did not exist
        when C{stat()} was called), or a C{stat_result} object that describes
        the last known status of the underlying file (or directory, as the case
        may be).  Trust me when I tell you that you do not want to use this
        attribute.  Instead, use the methods on L{FilePath} which give you
        information about it, like C{getsize()}, C{isdir()},
        C{getModificationTime()}, and so on.
    @type statinfo: L{int} or L{None} or L{os.stat_result}
    NFc