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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 file_format_name(self):
 """Return the current format name of the open bdf."""

        try:
            return BfdFormatNamesLong[self.file_format]
        except IndexError, err:
            raise BfdException("Invalid format specified (%d)" % self.file_format)