def loadfont(fontpath, private=True, enumerable=False):
    """
    Makes fonts located in file `fontpath` available to the font system.
    `private`     if True, other processes cannot see this font, and this 
                  font will be unloaded when the process dies
    `enumerable`  if True, this font will appear when enumerating fonts
    See https://msdn.microsoft.com/en-us/library/dd183327(VS.85).aspx
    """
if isinstance(fontpath, str):
    pathbuf = create_string_buffer(fontpath)
AddFontResourceEx = windll.gdi32.AddFontResourceExA
Truly custom font in Tkinter