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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 Verify(self, message, signature):
 """Verifies the signature for a given message."""

    siglen = len(signature)
    if siglen == 20:
      hash_algorithm = hashes.SHA1()
    elif siglen == 32:
      hash_algorithm = hashes.SHA256()
    else:
      raise VerificationError("Invalid signature length %d." % siglen)

    h = hmac.HMAC(self.key, hash_algorithm, backend=openssl.backend)
    h.update(message)
    try:
      h.verify(signature)
      return True
    except exceptions.InvalidSignature as e:
      raise VerificationError(e)