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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 get_workflows() -> dict: """Get dict of ALL known workflow definitions. Returns list[dict] """

    keys = DB.get_keys("workflow_definitions:*")
    known_workflows = dict()
    for key in keys:
        values = key.split(':')
        if values[1] not in known_workflows:
            known_workflows[values[1]] = list()
        known_workflows[values[1]].append(values[2])

    return known_workflows