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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 changed(self, src, path, dest):
 """Called whenever `path` is changed in the source folder `src`. `dest` is the output folder. The default implementation calls `build` after determining that the input file is newer than any of the outputs, or any of the outputs does not exist."""

        try:
            mtime = os.path.getmtime(os.path.join(src, path))
            self._build(src, path, dest, mtime)
        except EnvironmentError as e:
            logging.error("{0} is inaccessible: {1}".format(
                termcolor.colored(path, "yellow", attrs=["bold"]),
                e.args[0]
            ))