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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 getDescriptor(self, dir):
 		""" 		Detects the descriptor file for either an Unreal project or an Unreal plugin in the specified directory 		"""

		try:
			return self.getProjectDescriptor(dir)
		except:
			try:
				return self.getPluginDescriptor(dir)
			except:
				raise UnrealManagerException('could not detect an Unreal project or plugin in the directory "{}"'.format(dir))