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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 exists(fname):
 """ Determine whether a file exists. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/exists_c.html :param fname: Name of the file in question. :return: True if the file exists, False otherwise. :rtype: bool """

    fname = stypes.stringToCharP(fname)
    return bool(libspice.exists_c(fname))