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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 ToOBMag(self, wave, flux, area=None):
 """Convert to ``obmag``. .. math:: \\textnormal{obmag} = -2.5 \\; \\log(\\delta \\lambda \\; \\times \\; \\textnormal{area} \\; \\times \\; \\textnormal{photlam}) where :math:`\\delta \\lambda` represent bin widths derived from :func:`~pysynphot.binning.calculate_bin_edges` and :func:`~pysynphot.binning.calculate_bin_widths`, using the input wavelength values as bin centers. Parameters wave, flux : number or array_like Wavelength and flux values to be used for conversion. area : number or `None` Telescope collecting area. If not given, default value from :ref:`pysynphot-refdata` is used. Returns ------- result : number or array_like Converted values. """

        area = area if area else refs.PRIMARY_AREA
        bin_widths = \
            binning.calculate_bin_widths(binning.calculate_bin_edges(wave))
        arg = flux * bin_widths * area
        return -1.085736 * N.log(arg)