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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 _dump_spec(spec):
 """Dump bel specification dictionary using YAML Formats this with an extra indentation for lists to make it easier to use cold folding on the YAML version of the spec dictionary. """

    with open("spec.yaml", "w") as f:
        yaml.dump(spec, f, Dumper=MyDumper, default_flow_style=False)