the final step of the authenticate steps, where we load the values
           from config_data into the Configuration object.

           Parameters
           ==========
           config_data: a dictionary with configuration values (keys) to read
                        into self.config_values

def _load_config(self, config_data):
        """the final step of the authenticate steps, where we load the values
           from config_data into the Configuration object.

           Parameters
           ==========
           config_data: a dictionary with configuration values (keys) to read
                        into self.config_values

        """
        # Username and password are required.

        for item in [self.CONFIG_NAME_USER, self.CONFIG_NAME_KEY]:
            if item not in config_data:
                raise ValueError('Error: Missing %s in configuration.' % item)

        configuration = Configuration()

        # Add to the final configuration (required)

        configuration.username = config_data[self.CONFIG_NAME_USER]
        configuration.password = config_data[self.CONFIG_NAME_KEY]

        # Proxy

        if self.CONFIG_NAME_PROXY in config_data:
            configuration.proxy = config_data[self.CONFIG_NAME_PROXY]

        # Cert File

        if self.CONFIG_NAME_SSL_CA_CERT in config_data:
            configuration.ssl_ca_cert = config_data[self.
                                                    CONFIG_NAME_SSL_CA_CERT]

        # Keep config values with class instance, and load api client!

        self.config_values = config_data

        try:
            self.api_client = ApiClient(configuration)

        except Exception as error:

            if 'Proxy' in type(error).__name__:
                raise ValueError(
                    'The specified proxy ' +
                    config_data[self.CONFIG_NAME_PROXY] +
                    ' is not valid, please check your proxy settings')
            else:
                raise ValueError(
                    'Unauthorized: you must download an API key or export '
                    'credentials to the environment. Please see\n ' +
                    'https://github.com/Kaggle/kaggle-api#api-credentials ' +
                    'for instructions.')