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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 AddNewSignature(self, pattern, offset=None):
 """Adds a signature. Args: pattern (bytes):
 pattern of the signature. offset (int):
 offset of the signature. None is used to indicate the signature has no offset. A positive offset is relative from the start of the data a negative offset is relative from the end of the data. """

    self.signatures.append(Signature(pattern, offset=offset))