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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 placeholder(type_):
 """Returns the EmptyVal instance for the given type"""

    typetuple = type_ if isinstance(type_, tuple) else (type_,)
    if any in typetuple:
        typetuple = any
    if typetuple not in EMPTY_VALS:
        EMPTY_VALS[typetuple] = EmptyVal(typetuple)
    return EMPTY_VALS[typetuple]