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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 weld_str_lower(array):
 """Convert values to lowercase. Parameters array : numpy.ndarray or WeldObject Input data. Returns ------- WeldObject Representation of this computation. """

    obj_id, weld_obj = create_weld_object(array)

    weld_template = """map(
    {array},
    |e: vec[i8]|
        result(
            for(e,
                appender[i8],
                |c: appender[i8], j: i64, f: i8|
                    if(f > 64c && f < 91c,
                        merge(c, f + 32c),
                        merge(c, f))
            )
        )
)"""

    weld_obj.weld_code = weld_template.format(array=obj_id)

    return weld_obj