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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 arg_to_soql(arg):
 """ Perform necessary SOQL quoting on the arg. """

    conversion = sql_conversions.get(type(arg))
    if conversion:
        return conversion(arg)
    for type_ in subclass_conversions:
        if isinstance(arg, type_):
            return sql_conversions[type_](arg)
    return sql_conversions[str](arg)