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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 get_pidpath(rundir, process_type, name=None):
 """ Get the full path to the pid file for the given process type and name. """

    assert rundir, "rundir is not configured"
    path = os.path.join(rundir, '%s.pid' % process_type)
    if name:
        path = os.path.join(rundir, '%s.%s.pid' % (process_type, name))
    log.log('common', 'get_pidpath for type %s, name %r: %s'
            % (process_type, name, path))
    return path