How to use the birdears.urwid function in birdears

def Pad(weight=1):
    return ('weight',
            weight,
            urwid.BoxAdapter(urwid.SolidFill(SPACE_CHAR), height=FILL_HEIGHT))

def __init__(self, *args, **kwargs):

        self.footer_left = urwid.Text('r - Repeat question; q - Quit')
        self.footer_right = urwid.Text('--', align='right')
        header = urwid.AttrMap(urwid.Padding(urwid.Text('birdears ─ Functional'
                                                        ' Ear Training')),
                               'header')
        footer = urwid.AttrMap(urwid.Padding(urwid.Columns(widget_list=[
                            self.footer_left, self.footer_right])), 'footer')
        loading = urwid.Text('loading...')

        adapter = urwid.Filler(loading)

        super(TextUserInterfaceWidget, self).__init__(body=adapter,
                                                      header=header,
                                                      footer=footer)

def get_first_child(self):
        """Return the first TreeNode in the directory."""
        child_keys = self.get_child_keys()
        return self.get_child_node(child_keys[0])

    def get_last_child(self):
        """Return the last TreeNode in the directory."""
        child_keys = self.get_child_keys()
        return self.get_child_node(child_keys[-1])

    def has_children(self):
        """Does this node have any children?"""
        return len(self.get_child_keys())>0


class TreeWalker(urwid.ListWalker):
    """ListWalker-compatible class for displaying TreeWidgets

    positions are TreeNodes."""

    def __init__(self, start_from):
        """start_from: TreeNode with the initial focus."""
        self.focus = start_from

    def get_focus(self):
        widget = self.focus.get_widget()
        return widget, self.focus

    def set_focus(self, focus):
        self.focus = focus
        self._modified()

else:

            if KEY_PADS[first_chromatic.note]:
                weight = (KEY_PADS[first_chromatic.note]/2) + 1
                chromatic_keys.append(Pad(weight=weight))

            if not KEY_PADS[first_chromatic.note]:
                weight = 0.5
                chromatic_keys.append(Pad(weight=weight))

        self.key_index = {item.pitch_str: item
                          for item in chromatic_keys+diatonic_keys
                          if type(item).__name__ == 'KeyboardButton'}

        chromatic = urwid.Columns(widget_list=chromatic_keys, dividechars=1)
        diatonic = urwid.Columns(widget_list=diatonic_keys, dividechars=1)

        keyboard = urwid.Pile([chromatic, diatonic])
        box = urwid.LineBox(keyboard)

        super(Keyboard, self).__init__(body=box, min_height=10,
                                       *args, **kwargs)

def get_indented_widget(self):
        widget = self.get_inner_widget()
        if not self.is_leaf:
            widget = urwid.Columns([('fixed', 1,
                [self.unexpanded_icon, self.expanded_icon][self.expanded]),
                widget], dividechars=1)
        indent_cols = self.get_indent_cols()
        return urwid.Padding(widget,
            width=('relative', 100), left=indent_cols)

def __init__(self, *args, **kwargs):

        self.footer_left = urwid.Text('r - Repeat question; q - Quit')
        self.footer_right = urwid.Text('--', align='right')
        header = urwid.AttrMap(urwid.Padding(urwid.Text('birdears ─ Functional'
                                                        ' Ear Training')),
                               'header')
        footer = urwid.AttrMap(urwid.Padding(urwid.Columns(widget_list=[
                            self.footer_left, self.footer_right])), 'footer')
        loading = urwid.Text('loading...')

        adapter = urwid.Filler(loading)

        super(TextUserInterfaceWidget, self).__init__(body=adapter,
                                                      header=header,
                                                      footer=footer)

def __init__(self, top="", middle="", bottom="", pitch=None, *args,
                 **kwargs):

        self.pitch = pitch
        self.pitch_str = str(pitch)
        self.note_str = pitch.note

        top = self.note_str

        text = urwid.Text("{}\n{}\n{}".format(top, middle, bottom))
        fill = urwid.Filler(text)
        adapter = urwid.BoxAdapter(fill, height=3)
        pad = urwid.Padding(adapter)
        box = urwid.LineBox(pad)
        attr = urwid.AttrMap(w=box, attr_map='default')

        super(KeyboardButton, self).__init__(w=attr, *args, **kwargs)