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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 set_coords(self, x=0, y=0, z=0, t=0):
 """ set coords of agent in an arbitrary world """

        self.coords = {}
        self.coords['x'] = x
        self.coords['y'] = y
        self.coords['z'] = z
        self.coords['t'] = t