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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def read_config_file(self, config_data=None, quiet=False):
 """read_config_file is the first effort to get a username and key to authenticate to the Kaggle API. Since we can get the username and password from the environment, it's not required. Parameters ========== config_data: the Configuration object to save a username and password, if defined quiet: suppress verbose print of output (default is False) """

        if config_data is None:
            config_data = {}

        if os.path.exists(self.config):

            try:
                if os.name != 'nt':
                    permissions = os.stat(self.config).st_mode
                    if (permissions & 4) or (permissions & 32):
                        print(
                            'Warning: Your Kaggle API key is readable by other '
                            'users on this system! To fix this, you can run ' +
                            '\'chmod 600 {}\''.format(self.config))

                with open(self.config) as f:
                    config_data = json.load(f)
            except:
                pass

        else:

            # Warn the user that configuration will be reliant on environment
            if not quiet:
                print('No Kaggle API config file found, will use environment.')

        return config_data