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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_subfolders(self):
 """Retrieve all child Folders inside of this Folder. Raises: AuthError: Raised if Outlook returns a 401, generally caused by an invalid or expired access token. Returns: List[:class:`Folder <pyOutlook.core.folder.Folder>`] """

        headers = self.headers
        endpoint = 'https://outlook.office.com/api/v2.0/me/MailFolders/' + self.id + '/childfolders'

        r = requests.get(endpoint, headers=headers)

        if check_response(r):
            return self._json_to_folders(self.account, r.json())