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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 Assign(target, source):
 """Build an assignment statement"""

    if not isinstance(target, list):
        target = [target]
    if not isinstance(source, list):
        source.prefix = u" "
        source = [source]

    return Node(syms.atom,
                target + [Leaf(token.EQUAL, u"=", prefix=u" ")] + source)