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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 https_proxy(self):
 """Set ivy to use an https proxy. Expects a string of the form http://<host>:<port> """

    if os.getenv('HTTPS_PROXY'):
      return os.getenv('HTTPS_PROXY')
    if os.getenv('https_proxy'):
      return os.getenv('https_proxy')
    return self.get_options().https_proxy