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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 load_brain_metadata(proxy, include_fields):
 """Load values from the catalog metadata into a list of dictionaries """

    ret = {}
    for index in proxy.indexes():
        if index not in proxy:
            continue
        if include_fields and index not in include_fields:
            continue
        val = getattr(proxy, index)
        if val != Missing.Value:
            try:
                json.dumps(val)
            except:
                continue
            ret[index] = val
    return ret