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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 lx4num(string, first):
 """ Scan a string from a specified starting position for the end of a number. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/lx4num_c.html :param string: Any character string. :type string: str :param first: First character to scan from in string. :type first: int :return: last and nchar :rtype: tuple """

    string = stypes.stringToCharP(string)
    first = ctypes.c_int(first)
    last = ctypes.c_int()
    nchar = ctypes.c_int()
    libspice.lx4num_c(string, first, ctypes.byref(last), ctypes.byref(nchar))
    return last.value, nchar.value