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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 stpool(item, nth, contin, lenout=_default_len_out):
 """ Retrieve the nth string from the kernel pool variable, where the string may be continued across several components of the kernel pool variable. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/stpool_c.html :param item: Name of the kernel pool variable. :type item: str :param nth: Index of the full string to retrieve. :type nth: int :param contin: Character sequence used to indicate continuation. :type contin: str :param lenout: Available space in output string. :type lenout: int :return: A full string concatenated across continuations, The number of characters in the full string value. :rtype: tuple """

    item = stypes.stringToCharP(item)
    contin = stypes.stringToCharP(contin)
    nth = ctypes.c_int(nth)
    strout = stypes.stringToCharP(lenout)
    lenout = ctypes.c_int(lenout)
    found = ctypes.c_int()
    sizet = ctypes.c_int()
    libspice.stpool_c(item, nth, contin, lenout, strout, ctypes.byref(sizet),
                      ctypes.byref(found))
    return stypes.toPythonString(strout), sizet.value, bool(found.value)