    def replace_text(filepath, to_replace, replacement):
        """
        Replaces a string in a given file with another string

        :param file: the file in which the string has to be replaced
        :param to_replace: the string to be replaced in the file
        :param replacement: the string which replaces 'to_replace' in the file
        """
        with open(filepath) as file:
            s = file.read()
        s = s.replace(to_replace, replacement)
        with open(filepath, 'w') as file:
            file.write(s)