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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 pcklof(filename):
 """ Load a binary PCK file for use by the readers. Return the handle of the loaded file which is used by other PCK routines to refer to the file. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/pcklof_c.html :param filename: Name of the file to be loaded. :type filename: str :return: Loaded file's handle. :rtype: int """

    filename = stypes.stringToCharP(filename)
    handle = ctypes.c_int()
    libspice.pcklof_c(filename, ctypes.byref(handle))
    return handle.value