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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 flatten_(structure):
 """Combine all leaves of a nested structure into a tuple. The nested structure can consist of any combination of tuples, lists, and dicts. Dictionary keys will be discarded but values will ordered by the sorting of the keys. Args: structure: Nested structure. Returns: Flat tuple. """

  if isinstance(structure, dict):
    if structure:
      structure = zip(*sorted(structure.items(), key=lambda x: x[0]))[1]
    else:
      # Zip doesn't work on an the items of an empty dictionary.
      structure = ()
  if isinstance(structure, (tuple, list)):
    result = []
    for element in structure:
      result += flatten_(element)
    return tuple(result)
  return (structure,)