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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 eps(self):
 	"""Print the canvas to a postscript file"""


        import tkFileDialog,tkMessageBox
        filename=tkFileDialog.asksaveasfilename(message="save postscript to file",filetypes=['eps','ps'])
	if filename is None:
	    return 

	self.postscript(file=filename)