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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 decrypt_block(self, cipherText):
 """Decrypt a 16-byte block of data. NOTE: This function was formerly called `decrypt`, but was changed when support for decrypting arbitrary-length strings was added. Args: cipherText (str):
 16-byte data. Returns: 16-byte str. Raises: TypeError if CamCrypt object has not been initialized. ValueError if `cipherText` is not BLOCK_SIZE (i.e. 16) bytes. """

    if not self.initialized:
      raise TypeError("CamCrypt object has not been initialized")
    if len(cipherText) != BLOCK_SIZE:
      raise ValueError("cipherText must be %d bytes long (received %d bytes)" %
                       (BLOCK_SIZE, len(cipherText)))
    plain = ctypes.create_string_buffer(BLOCK_SIZE)
    self.decblock(self.bitlen, cipherText, self.keytable, plain)
    return plain.raw