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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 is_monotonic(full_list):
 """ Determine whether elements in a list are monotonic. ie. unique elements are clustered together. ie. [5,5,3,4] is, [5,3,5] is not. """

    prev_elements = set({full_list[0]})
    prev_item = full_list[0]

    for item in full_list:
        if item != prev_item:
            if item in prev_elements:
                return False
            prev_item = item
            prev_elements.add(item)

    return True