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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 deleteSNPs(setName) : 	"""deletes a set of polymorphisms"""

	con = conf.db
	try :
		SMaster = SNPMaster(setName = setName)
		con.beginTransaction()
		SNPType = SMaster.SNPType
		con.delete(SNPType, 'setName = ?', (setName,))
		SMaster.delete()
		con.endTransaction()
	except KeyError :
		raise KeyError("Can't delete the setName %s because i can't find it in SNPMaster, maybe there's not set by that name" % setName)
		#~ printf("can't delete the setName %s because i can't find it in SNPMaster, maybe there's no set by that name" % setName)
		return False
	return True