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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 writePIDFile(self):
 """ Write a the pid of this process to a file in the jobstore. Overwriting the current contents of pid.log is a feature, not a bug of this method. Other methods will rely on always having the most current pid available. So far there is no reason to store any old pids. """

        with self._jobStore.writeSharedFileStream('pid.log') as f:
            f.write(str(os.getpid()).encode('utf-8'))