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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 is_volume(self):
 """ Check if a mesh has all the properties required to represent a valid volume, rather than just a surface. These properties include being watertight, having consistent winding and outward facing normals. Returns --------- valid : bool Does the mesh represent a volume """

        valid = bool(self.is_watertight and
                     self.is_winding_consistent and
                     np.isfinite(self.center_mass).all() and
                     self.volume > 0.0)
        return valid