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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 humanized_model_to_dict(instance, readonly_fields, fields=None, exclude=None):
 """ Returns a dict containing the humanized data in ``instance`` suitable for passing as a Form's ``initial`` keyword argument. ``fields`` is an optional list of field names. If provided, only the named fields will be included in the returned dict. ``exclude`` is an optional list of field names. If provided, the named fields will be excluded from the returned dict, even if they are listed in the ``fields`` argument. """

    opts = instance._meta
    data = {}
    for f in itertools.chain(opts.concrete_fields, opts.private_fields, opts.many_to_many):
        if not getattr(f, 'editable', False):
            continue
        if fields and f.name not in fields:
            continue
        if f.name not in readonly_fields:
            continue
        if exclude and f.name in exclude:
            continue

        if f.humanized:
            data[f.name] = f.humanized(getattr(instance, f.name), instance)
    return data