For JSON, the source it the file path

def load_config(self, config_source, parameters_source):
        """For JSON, the source it the file path"""
        with open(config_source) as config_source:
            config_raw = config_source.read()
            """Replace the parameters"""
            pattern = "(%[a-zA-Z_0-9]*%)"

            self.parameters = {}
            """Parameteres from file"""
            if os.path.isfile(parameters_source):
                self.parameters.update(self.load_parameters(parameters_source))

            """Overwrite parameteres with the environment variables"""
            self.parameters.update(os.environ)

            replaced_config = re.sub(pattern=pattern, repl=self._replace_function, string=config_raw)
            return json.loads(replaced_config)