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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 unpack_ip(fourbytes):
 	"""Converts an ip address given in a four byte string in network 	byte order to a string in dotted notation. 	'100.101.97.100' 	Traceback (most recent call last):
 	ValueError: given buffer is not exactly four bytes long 	@type fourbytes: bytes 	@rtype: str 	@raises ValueError: for bad input 	"""

	if not isinstance(fourbytes, bytes):
		raise ValueError("given buffer is not a string")
	if len(fourbytes) != 4:
		raise ValueError("given buffer is not exactly four bytes long")
	return ".".join([str(x) for x in bytes_to_int_seq(fourbytes)])