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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 wnintd(a, b):
 """ Place the intersection of two double precision windows into a third window. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/wnintd_c.html :param a: Input window A. :type a: spiceypy.utils.support_types.SpiceCell :param b: Input window B. :type b: spiceypy.utils.support_types.SpiceCell :return: Intersection of a and b. :rtype: spiceypy.utils.support_types.SpiceCell """

    assert isinstance(a, stypes.SpiceCell)
    assert b.dtype == 1
    assert isinstance(b, stypes.SpiceCell)
    assert a.dtype == 1
    c = stypes.SpiceCell.double(b.size + a.size)
    libspice.wnintd_c(ctypes.byref(a), ctypes.byref(b), ctypes.byref(c))
    return c