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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 where_stmt_handle(tokens):
 """Process a where statement."""

    internal_assert(len(tokens) == 2, "invalid where statement tokens", tokens)
    base_stmt, assignment_stmts = tokens
    stmts = list(assignment_stmts) + [base_stmt]
    return "\n".join(stmts) + "\n"