from sympy.utilities.decorator import doctest_depends_on

__doctest_requires__ = ...
def system_default_viewer(fname, fmt) -> None:
    ...

def pyglet_viewer(fname, fmt) -> None:
    ...

@doctest_depends_on(exe=('latex', 'dvipng'), modules=('pyglet', ), disable_viewers=('evince', 'gimp', 'superior-dvi-viewer'))
def preview(expr, output=..., viewer=..., euler=..., packages=..., filename=..., outputbuffer=..., preamble=..., dvioptions=..., outputTexFile=..., extra_preamble=..., fontsize=..., **latex_settings) -> None:
    ...

