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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 create_child_folder(self, folder_name):
 """Creates a child folder within the Folder it is called from and returns the new Folder object. Args: folder_name: The name of the folder to create Returns: :class:`Folder <pyOutlook.core.folder.Folder>` """

        headers = self.headers
        endpoint = 'https://outlook.office.com/api/v2.0/me/MailFolders/' + self.id + '/childfolders'
        payload = '{ "DisplayName": "' + folder_name + '"}'

        r = requests.post(endpoint, headers=headers, data=payload)

        if check_response(r):
            return_folder = r.json()
            return self._json_to_folder(self.account, return_folder)