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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 get_folder_contents_iter(self, uri):
 """Return iterator for directory contents. uri -- mediafire URI Example: for item in get_folder_contents_iter('mf:///Documents'):
 print(item) """

        resource = self.get_resource_by_uri(uri)

        if not isinstance(resource, Folder):
            raise NotAFolderError(uri)

        folder_key = resource['folderkey']

        for item in self._folder_get_content_iter(folder_key):
            if 'filename' in item:
                # Work around https://mediafire.mantishub.com/view.php?id=5
                # TODO: remove in 1.0
                if ".patch." in item['filename']:
                    continue
                yield File(item)
            elif 'name' in item:
                yield Folder(item)