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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_keys(self):
 """ Get the Twitter API keys. Order of precedence is command line, environment, config file. Return True if all the keys were found and False if not. """

        env = os.environ.get
        if not self.consumer_key:
            self.consumer_key = env('CONSUMER_KEY')
        if not self.consumer_secret:
            self.consumer_secret = env('CONSUMER_SECRET')
        if not self.access_token:
            self.access_token = env('ACCESS_TOKEN')
        if not self.access_token_secret:
            self.access_token_secret = env('ACCESS_TOKEN_SECRET')

        if self.config and not (self.consumer_key and
                                self.consumer_secret and
                                self.access_token and
                                self.access_token_secret):
            self.load_config()