def find_location(self, root, path, prefix=None):
        """
        Finds a requested static file in a location, returning the found
        absolute path (or ``None`` if no match).
        """
        if prefix:
            prefix = '%s%s' % (prefix, os.sep)
            if not path.startswith(prefix):
                return None
            path = path[len(prefix):]
        path = safe_join(root, path)
        if os.path.exists(path):
            return path
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/contrib/staticfiles/finders.py/FileSystemFinder.find_location/original