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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 set_azure_secret_access_key(config_fpath, container, az_secret_access_key):
 """Write the ECS access key id to the dtool config file. :param config_fpath: path to the dtool config file :param container: azure storage container name :param az_secret_access_key: azure secret access key for the container """

    key = AZURE_KEY_PREFIX + container
    return write_config_value_to_file(key, az_secret_access_key, config_fpath)