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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def draw_circuit(circuit, filename, direction = 'lr', hunit = HUNIT, vunit = VUNIT, rhmargin = RHMARGIN, rvmargin = RVMARGIN, rpermutation_length = RPLENGTH, draw_boxes = True, permutation_arrows = False):
 """ Generate a graphic representation of circuit and store them in a file. The graphics format is determined from the file extension. :param circuit: The circuit expression :type circuit: ca.Circuit :param filename: A filepath to store the output image under. The file name suffix determines the output graphics format :type filename: str :param direction: The horizontal direction of laying out series products. One of ``'lr'`` and ``'rl'``. This option overrides a negative value for ``hunit``, default = ``'lr'`` :param hunit: The horizontal length unit, default = ``HUNIT`` :type hunit: float :param vunit: The vertical length unit, default = ``VUNIT`` :type vunit: float :param rhmargin: relative horizontal margin, default = ``RHMARGIN`` :type rhmargin: float :param rvmargin: relative vertical margin, default = ``RVMARGIN`` :type rvmargin: float :param rpermutation_length: the relative length of a permutation circuit, default = ``RPLENGTH`` :type rpermutation_length: float :param draw_boxes: Whether to draw indicator boxes to denote subexpressions (Concatenation, SeriesProduct, etc.), default = ``True`` :type draw_boxes: bool :param permutation_arrows: Whether to draw arrows within the permutation visualization, default = ``False`` :type permutation_arrows: bool :return: ``True`` if printing was successful, ``False`` if not. :rtype: bool """



    if direction == 'lr':
        hunit = abs(hunit)

    elif direction == 'rl':
        hunit = -abs(hunit)
    try:
        c, dims, c_in, c_out = draw_circuit_canvas(circuit, hunit = hunit, vunit = vunit,
                                            rhmargin = rhmargin, rvmargin = rvmargin,
                                            rpermutation_length = rpermutation_length,
                                            draw_boxes = draw_boxes,
                                            permutation_arrows = permutation_arrows)
    except ValueError as e:
        print( ("No graphics returned for circuit {!r}".format(circuit)))
        return False
    ps_suffixes = ['.pdf', '.eps', '.ps']
    gs_suffixes = ['.png', '.jpg']
    if any(filename.endswith(suffix) for suffix in ps_suffixes):
        c.writetofile(filename)
    elif any(filename.endswith(suffix) for suffix in gs_suffixes):
        if GS is None:
            raise FileNotFoundError(
                "No Ghostscript executable available. Ghostscript is required for "
                "rendering to {}.".format(", ".join(gs_suffixes))
            )
        c.writeGSfile(filename, gs=GS)
    return True