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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 gsim(value):
 """ Convert a string in TOML format into a GSIM instance [BooreAtkinson2011] """

    if not value.startswith('['):  # assume the GSIM name
        value = '[%s]' % value
    [(gsim_name, kwargs)] = toml.loads(value).items()
    minimum_distance = float(kwargs.pop('minimum_distance', 0))
    if gsim_name == 'FromFile':
        return FromFile()
    try:
        gsim_class = registry[gsim_name]
    except KeyError:
        raise ValueError('Unknown GSIM: %s' % gsim_name)
    gs = gsim_class(**kwargs)
    gs._toml = '\n'.join(line.strip() for line in value.splitlines())
    gs.minimum_distance = minimum_distance
    return gs