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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 coerce_to_list(val):
 """ For parameters that can take either a single string or a list of strings, this function will ensure that the result is a list containing the passed values. """

    if val:
        if not isinstance(val, (list, tuple)):
            val = [val]
    else:
        val = []
    return val