<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def getEngineVersion(self, outputFormat = 'full'):
 		""" 		Returns the version number of the latest installed version of UE4 		"""

		version = self._getEngineVersionDetails()
		formats = {
			'major': version['MajorVersion'],
			'minor': version['MinorVersion'],
			'patch': version['PatchVersion'],
			'full': '{}.{}.{}'.format(version['MajorVersion'], version['MinorVersion'], version['PatchVersion']),
			'short': '{}.{}'.format(version['MajorVersion'], version['MinorVersion'])
		}
		
		# Verify that the requested output format is valid
		if outputFormat not in formats:
			raise Exception('unreconised version output format "{}"'.format(outputFormat))
		
		return formats[outputFormat]