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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 deploy_namespace(filename, module_name, hash_check=True, auth=None):
 """Deploy a file to the Artifactory BEL namespace cache. :param str filename: The physical path :param str module_name: The name of the module to deploy to :param bool hash_check: Ensure the hash is unique before deploying :param tuple[str] auth: A pair of (str username, str password) to give to the auth keyword of the constructor of :class:`artifactory.ArtifactoryPath`. Defaults to the result of :func:`get_arty_auth`. :return: The resource path, if it was deployed successfully, else none. :rtype: Optional[str] """

    return _deploy_helper(
        filename,
        module_name,
        get_namespace_module_url,
        get_namespace_today,
        hash_check=hash_check,
        auth=auth
    )