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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 from_dict(config):
        '''
        Instantiate a new ProxyConfig from a dictionary that represents a
        client configuration, as described in `the documentation`_.

        .. _the documentation:
            https://docs.docker.com/network/proxy/#configure-the-docker-client
        '''
        return ProxyConfig(
            http=config.get('httpProxy'),
            https=config.get('httpsProxy'),
            ftp=config.get('ftpProxy'),
            no_proxy=config.get('noProxy'),
        )