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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 lock_file(self, fpath, after_setup=False, wait=False):
 """Locks the specified file. :param str|unicode fpath: File path. :param bool after_setup: True - after logging/daemon setup False - before starting :param bool wait: True - wait if locked False - exit if locked """

        command = 'flock-wait' if wait else 'flock'

        if after_setup:
            command = '%s2' % command

        self._set(command, fpath)

        return self._section