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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 filter_grounded_only(stmts_in, **kwargs):
 """Filter to statements that have grounded agents. Parameters stmts_in : list[indra.statements.Statement] A list of statements to filter. score_threshold : Optional[float] If scored groundings are available in a list and the highest score if below this threshold, the Statement is filtered out. save : Optional[str] The name of a pickle file to save the results (stmts_out) into. remove_bound: Optional[bool] If true, removes ungrounded bound conditions from a statement. If false (default), filters out statements with ungrounded bound conditions. Returns ------- stmts_out : list[indra.statements.Statement] A list of filtered statements. """

    remove_bound = kwargs.get('remove_bound', False)

    logger.info('Filtering %d statements for grounded agents...' % 
                len(stmts_in))
    stmts_out = []
    score_threshold = kwargs.get('score_threshold')
    for st in stmts_in:
        grounded = True
        for agent in st.agent_list():
            if agent is not None:
                criterion = lambda x: _agent_is_grounded(x, score_threshold)
                if not criterion(agent):
                    grounded = False
                    break
                if not isinstance(agent, Agent):
                    continue
                if remove_bound:
                    _remove_bound_conditions(agent, criterion)
                elif _any_bound_condition_fails_criterion(agent, criterion):
                    grounded = False
                    break
        if grounded:
            stmts_out.append(st)
    logger.info('%d statements after filter...' % len(stmts_out))
    dump_pkl = kwargs.get('save')
    if dump_pkl:
        dump_statements(stmts_out, dump_pkl)
    return stmts_out