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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 site_param(dic):
 """ Convert a dictionary site_model_param -> string into a dictionary of valid casted site parameters. """

    new = {}
    for name, val in dic.items():
        if name == 'vs30Type':
            # avoid "Unrecognized parameter vs30Type"
            new['vs30measured'] = val == 'measured'
        elif name not in site.site_param_dt:
            raise ValueError('Unrecognized parameter %s' % name)
        else:
            new[name] = val
    return new