Main function that handle SNMP's pass_persist protocol, called by
		the start method.
		Direct call is unnecessary.

def main_passpersist(self):
		"""
		Main function that handle SNMP's pass_persist protocol, called by
		the start method.
		Direct call is unnecessary.
		"""
		line = sys.stdin.readline().strip()
		if not line:
			raise EOFError()

		if 'PING' in line:
			print("PONG")
		elif 'getnext' in line:
			oid = self.cut_oid(sys.stdin.readline().strip())
			if oid is None:
				print("NONE")
			elif oid == "":
				# Fallback to the first entry
				print(self.get_first())
			else:
				print(self.get_next(oid))
		elif 'get' in line:
			oid = self.cut_oid(sys.stdin.readline().strip())
			if oid is None:
				print("NONE")
			else:
				print(self.get(oid))
		elif 'set' in line:
			oid = sys.stdin.readline().strip()
			typevalue = sys.stdin.readline().strip()
			self.set(oid, typevalue)
		elif 'DUMP' in line: # Just for debbuging
			from pprint import pprint
			pprint(self.data)
		else:
			print("NONE")

		sys.stdout.flush()