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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 plot(self,**kwargs):
 """ get a cheap plot of the Vario2d Parameters **kwargs : (dict) keyword arguments to use for plotting Returns ------- ax : matplotlib.pyplot.axis Note ---- optional arguments in kwargs include "ax" (existing matplotlib.pyplot.axis). Other kwargs are passed to matplotlib.pyplot.plot() """

        try:
            import matplotlib.pyplot as plt
        except Exception as e:
            raise Exception("error importing matplotlib: {0}".format(str(e)))

        ax = kwargs.pop("ax",plt.subplot(111))
        x = np.linspace(0,self.a*3,100)
        y = self.inv_h(x)
        ax.set_xlabel("distance")
        ax.set_ylabel("$\gamma$")
        ax.plot(x,y,**kwargs)
        return ax