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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 swpool(agent, nnames, lenvals, names):
 """ Add a name to the list of agents to notify whenever a member of a list of kernel variables is updated. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/swpool_c.html :param agent: The name of an agent to be notified after updates. :type agent: str :param nnames: The number of variables to associate with agent. :type nnames: int :param lenvals: Length of strings in the names array. :type lenvals: int :param names: Variable names whose update causes the notice. :type names: list of strs. """

    agent = stypes.stringToCharP(agent)
    nnames = ctypes.c_int(nnames)
    lenvals = ctypes.c_int(lenvals)
    names = stypes.listToCharArray(names)
    libspice.swpool_c(agent, nnames, lenvals, names)