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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 read_private_key_file(pkey_file, pkey_password=None, key_type=None, logger=None):
 """ Get SSH Public key from a private key file, given an optional password Arguments: pkey_file (str):
 File containing a private key (RSA, DSS or ECDSA) Keyword Arguments: pkey_password (Optional[str]):
 Password to decrypt the private key logger (Optional[logging.Logger]) Return: paramiko.Pkey """

        ssh_pkey = None
        for pkey_class in (key_type,) if key_type else (
            paramiko.RSAKey,
            paramiko.DSSKey,
            paramiko.ECDSAKey,
            paramiko.Ed25519Key
        ):
            try:
                ssh_pkey = pkey_class.from_private_key_file(
                    pkey_file,
                    password=pkey_password
                )
                if logger:
                    logger.debug('Private key file ({0}, {1}) successfully '
                                 'loaded'.format(pkey_file, pkey_class))
                break
            except paramiko.PasswordRequiredException:
                if logger:
                    logger.error('Password is required for key {0}'
                                 .format(pkey_file))
                break
            except paramiko.SSHException:
                if logger:
                    logger.debug('Private key file ({0}) could not be loaded '
                                 'as type {1} or bad password'
                                 .format(pkey_file, pkey_class))
        return ssh_pkey