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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 inject_pid(self, data):
 """Inject context PID in the RECID field."""

        # Remove already deserialized "pid" field
        pid_value = data.pop('pid', None)
        if pid_value:
            pid_field = current_app.config['PIDSTORE_RECID_FIELD']
            data.setdefault(pid_field, pid_value)
        return data