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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 ordd(item, inset):
 """ The function returns the ordinal position of any given item in a double precision set. If the item does not appear in the set, the function returns -1. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/ordd_c.html :param item: An item to locate within a set. :type item: float :param inset: A set to search for a given item. :type inset: SpiceDoubleCell :return: the ordinal position of item within the set :rtype: int """

    assert isinstance(inset, stypes.SpiceCell)
    assert inset.is_double()
    item = ctypes.c_double(item)
    return libspice.ordd_c(item, ctypes.byref(inset))