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

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