def __init__(self, import_name, exception):
        self.import_name = import_name
        self.exception = exception
        msg = _import_string_error
        name = ''
        tracked = []
        for part in import_name.split('.'):
            name += (name and '.') + part
            imported = import_string(name, silent=True)
            if imported:
                tracked.append((name, imported.__file__))
            else:
                track = ['- %r found in %r.' % rv for rv in tracked]
                track.append('- %r not found.' % name)
                msg = msg % (import_name, exception.__class__.__name__,
                             str(exception), '\n'.join(track))
                break

        Exception.__init__(self, msg)
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/webapp2-2.5.1/webapp2.py/ImportStringError.__init__/original