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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 mgl_seq(x):
 """ Sequence whose sum is the Madhava-Gregory-Leibniz series. Returns ------- An endless sequence that has the property ``atan(x) = sum(mgl_seq(x))``. Usually you would use the ``atan()`` function, not this one. """

  odd_numbers = thub(count(start=1, step=2), 2)
  return Stream(1, -1) * x ** odd_numbers / odd_numbers