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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 list_and_add(a, b):
 """ Concatenate anything into a list. Args: a: the first thing b: the second thing Returns: list. All the things in a list. """

    if not isinstance(b, list):
        b = [b]
    if not isinstance(a, list):
        a = [a]
    return a + b