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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 process_alias_create_namespace(namespace):
 """ Validate input arguments when the user invokes 'az alias create'. Args: namespace: argparse namespace object. """

    namespace = filter_alias_create_namespace(namespace)
    _validate_alias_name(namespace.alias_name)
    _validate_alias_command(namespace.alias_command)
    _validate_alias_command_level(namespace.alias_name, namespace.alias_command)
    _validate_pos_args_syntax(namespace.alias_name, namespace.alias_command)