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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 wncond(left, right, window):
 """ Contract each of the intervals of a double precision window. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/wncond_c.html :param left: Amount added to each left endpoint. :type left: float :param right: Amount subtracted from each right endpoint. :type right: float :param window: Window to be contracted :type window: spiceypy.utils.support_types.SpiceCell :return: Contracted Window. :rtype: spiceypy.utils.support_types.SpiceCell """

    assert isinstance(window, stypes.SpiceCell)
    assert window.dtype == 1
    left = ctypes.c_double(left)
    right = ctypes.c_double(right)
    libspice.wncond_c(left, right, ctypes.byref(window))
    return window