code: def read_spec(filename, verbose=False):
    
    contents = None
    with open(filename, 'r') as f:
      contents = yaml.load(f)
      if contents is None:
        raise Exception("Empty yaml file: %s." % filename)
      try:
        s.package_schema(contents)
      except Exception as e:
        sys.stderr.write("Invalid SBP YAML specification: %s.\n" % filename)
        raise e
    return contents
docs: Read an SBP specification.
  
    Parameters
    ----------
    filename : str
      Local filename for specification.
    verbose : bool
      Print out some debugging info
  
    Returns
    ----------
  
    Raises
    ----------
    Exception
      On empty file.
    yaml.YAMLError
      On Yaml parsing error
    voluptuous.Invalid
      On invalid SBP schema