code: def scale(self, x, y=None, z=None):
          "Uniform scale, if only sx argument is specified"
          if y is None:
              y = x
          if z is None:
              z = x
          m = self
          for col in range(4):
              # Only the top three rows
              m[0,col] *= x
              m[1,col] *= y
              m[2,col] *= z
          return self scale(self, x, y=None, z=None):
          "Uniform scale, if only sx argument is specified"
          if y is None:
              y = x
          if z is None:
              z = x
          m = self
          for col in range(4):
              # Only the top three rows
              m[0,col] *= x
              m[1,col] *= y
              m[2,col] *= z
          return self
docs: Uniform scale, if only sx argument is specified