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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 pickle_load(cls, filepath, spectator_mode=True, remove_lock=False):
 """ Loads the object from a pickle file and performs initial setup. Args: filepath: Filename or directory name. It filepath is a directory, we scan the directory tree starting from filepath and we read the first pickle database. Raise RuntimeError if multiple databases are found. spectator_mode: If True, the nodes of the flow are not connected by signals. This option is usually used when we want to read a flow in read-only mode and we want to avoid callbacks that can change the flow. remove_lock: True to remove the file lock if any (use it carefully). """

        if os.path.isdir(filepath):
            # Walk through each directory inside path and find the pickle database.
            for dirpath, dirnames, filenames in os.walk(filepath):
                fnames = [f for f in filenames if f == cls.PICKLE_FNAME]
                if fnames:
                    if len(fnames) == 1:
                        filepath = os.path.join(dirpath, fnames[0])
                        break  # Exit os.walk
                    else:
                        err_msg = "Found multiple databases:\n %s" % str(fnames)
                        raise RuntimeError(err_msg)
            else:
                err_msg = "Cannot find %s inside directory %s" % (cls.PICKLE_FNAME, filepath)
                raise ValueError(err_msg)

        if remove_lock and os.path.exists(filepath + ".lock"):
            try:
                os.remove(filepath + ".lock")
            except:
                pass

        with FileLock(filepath):
            with open(filepath, "rb") as fh:
                flow = pmg_pickle_load(fh)

        # Check if versions match.
        if flow.VERSION != cls.VERSION:
            msg = ("File flow version %s != latest version %s\n."
                   "Regenerate the flow to solve the problem " % (flow.VERSION, cls.VERSION))
            warnings.warn(msg)

        flow.set_spectator_mode(spectator_mode)

        # Recompute the status of each task since tasks that
        # have been submitted previously might be completed.
        flow.check_status()
        return flow