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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 is_dll(self):
 """Check whether the file is a standard DLL. This will return true only if the image has the IMAGE_FILE_DLL flag set. """


        DLL_flag = IMAGE_CHARACTERISTICS['IMAGE_FILE_DLL']

        if ( DLL_flag & self.FILE_HEADER.Characteristics) == DLL_flag:
            return True

        return False