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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 _build_list_params(param_name, key, values):
 """Builds a list of POST parameters from a list or single value."""

        params = {}
        if hasattr(values, '__iter__'):
            index = 0
            for value in values:
                params[str(param_name) + '[' + str(index) + '].' + str(key)] = str(value)
                index += 1
        else:
            params[str(param_name) + '[0].' + str(key)] = str(values)
        return params