How to use the pympress.builder function in pympress

def show_shortcuts(self, *args):
        """ Display the shortcuts window.
        """
        # Use a different builder to load and be able to release the shortcuts window
        shortcuts_builder = builder.Builder()
        shortcuts_builder.load_ui('shortcuts')
        self.shortcuts_window = shortcuts_builder.get_object('shortcuts_window')

        for command, shortcut_list in self.config.items('shortcuts'):
            display_shortcut = shortcuts_builder.get_object('shortcut_' + command)
            if display_shortcut is not None:
                display_shortcut.props.accelerator = shortcut_list

        self.shortcuts_window.set_transient_for(self.p_win)
        self.shortcuts_window.show_all()
        self.shortcuts_window.present()

import gi
import cairo
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk, Gdk, GLib, Pango

import mimetypes
from collections import defaultdict

from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler

from pympress import document, builder, config
from pympress.media_overlays.base import VideoOverlay


class TimingReport(builder.Builder):
    #: `list` of time at which each page was reached
    page_time = []
    #: `int` the time at which the clock was reset
    reset_time = -1
    #: The :class:`~Gtk.TreeView` containing the timing data to display in the dialog.
    timing_treeview = None
    #: A :class:`~Gtk.Dialog` to contain the timing to show.
    time_report_dialog = None

    def __init__(self, parent):
        super(TimingReport, self).__init__()
        self.load_ui('time_report_dialog')
        self.time_report_dialog.set_transient_for(parent.p_win)
        self.time_report_dialog.add_button(Gtk.STOCK_CLOSE, Gtk.ResponseType.CLOSE)
        self.connect_signals(self)

logger = logging.getLogger(__name__)

import os.path
import sys

import gi
import cairo
gi.require_version('Gtk', '3.0')
from gi.repository import GObject, Gtk, Gdk, GLib, GdkPixbuf


from pympress import document, surfacecache, util, pointer, scribble, config, builder, talk_time, extras, editable_label



class UI(builder.Builder):
    """ Pympress GUI management.
    """
    #: Content window, as a :class:`~Gtk.Window` instance.
    c_win = None
    #: :class:`~Gtk.AspectFrame` for the Content window.
    c_frame = None
    #: :class:`~Gtk.DrawingArea` for the Content window.
    c_da = None
    #: :class:`~Gtk.CheckMenuItem` that shows whether the c_win is fullscreen
    pres_fullscreen = None

    #: Presenter window, as a :class:`~Gtk.Window` instance.
    p_win = None
    #: :class:`~Gtk.Box` for the Presenter window.
    p_central = None
    #: :class:`~Gtk.AspectFrame` for the current slide in the Presenter window.

"""

from __future__ import print_function, unicode_literals

import logging
logger = logging.getLogger(__name__)

import gi
import cairo
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk, Gdk

from pympress import builder, surfacecache, document, extras


class Scribbler(builder.Builder):
    #: Whether we are displaying the interface to scribble on screen and the overlays containing said scribbles
    scribbling_mode = False
    #: `list` of scribbles to be drawn, as tuples of color :class:`~Gdk.RGBA`, width `int`, and a `list` of points.
    scribble_list = []
    #: Whether the current mouse movements are drawing strokes or should be ignored
    scribble_drawing = False
    #: :class:`~Gdk.RGBA` current color of the scribbling tool
    scribble_color = Gdk.RGBA()
    #: `int` current stroke width of the scribbling tool
    scribble_width = 1

    #: :class:`~Gtk.HBox` that is replaces normal panes when scribbling is toggled, contains buttons and scribble drawing area
    scribble_overlay = None
    #: :class:`~Gtk.DrawingArea` for the scribbles in the Presenter window. Actually redraws the slide.
    scribble_p_da = None
    #: :class:`~Gtk.EventBox` for the scribbling in the Content window, captures freehand drawing

Args:
        window (:class:`~Gdk.Window`): The window for which we want to get the handle

    Returns:
        The handle to the win32 window
    """
    # get the c gpointer of the gdk window
    ctypes.pythonapi.PyCapsule_GetPointer.restype = ctypes.c_void_p
    ctypes.pythonapi.PyCapsule_GetPointer.argtypes = [ctypes.py_object]
    drawingarea_gpointer = ctypes.pythonapi.PyCapsule_GetPointer(window.__gpointer__, None)
    # get the win32 handle
    gdkdll = ctypes.CDLL('libgdk-3-0.dll')
    return gdkdll.gdk_win32_window_get_handle(drawingarea_gpointer)


class VideoOverlay(builder.Builder):
    """ Simple Video widget.

    Args:
        container (:class:`~Gtk.Overlay`): The container with the slide, at the top of which we add the movie area
        show_controls (`bool`): whether to display controls on the video player
        page_type (:class:`~pympress.document.PdfPage`): the part of the page to display
        relative_margins (:class:`~Poppler.Rectangle`): the margins defining the position of the video in the frame.
    """
    #: :class:`~Gtk.Overlay` that is the parent of the VideoOverlay widget.
    parent = None
    #: :class:`~Gtk.VBox` that contains all the elements to be overlayed.
    media_overlay = None
    #: A :class:`~Gtk.HBox` containing a toolbar with buttons and :attr:`~progress` the progress bar
    toolbar = None
    #: :class:`~Gtk.Scale` that is the progress bar in the controls toolbar - if we have one.
    progress = None