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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 set_log_file_extension(self, logFileExtension):
 """ Set the log file extension. :Parameters: #. logFileExtension (string):
 Logging file extension. A logging file full name is set as logFileBasename.logFileExtension """

        assert isinstance(logFileExtension, basestring), "logFileExtension must be a basestring"
        assert len(logFileExtension), "logFileExtension can't be empty"
        if logFileExtension[0] == ".":
            logFileExtension = logFileExtension[1:]
        assert len(logFileExtension), "logFileExtension is not allowed to be single dot"
        if logFileExtension[-1] == ".":
            logFileExtension = logFileExtension[:-1]
        assert len(logFileExtension), "logFileExtension is not allowed to be double dots"
        self.__logFileExtension = logFileExtension
        # set log file name
        self.__set_log_file_name()