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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_captcha_key(self, captcha_image_url):
 """Read CAPTCHA key from user input"""


        if self.interactive:
            print('Open CAPTCHA image url in your browser and enter it below: ',
                  captcha_image_url)
            captcha_key = raw_input('Enter CAPTCHA key: ')
            return captcha_key
        else:
            raise VkAuthError(
                'Captcha is required. Use interactive mode to enter it '
                'manually')