github.com/apache/beam/sdks/v2@v2.48.2/python/apache_beam/examples/snippets/transforms/aggregation/max.py (about)

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    18  
    19  # pytype: skip-file
    20  
    21  
    22  def max_globally(test=None):
    23    # [START max_globally]
    24    import apache_beam as beam
    25  
    26    with beam.Pipeline() as pipeline:
    27      max_element = (
    28          pipeline
    29          | 'Create numbers' >> beam.Create([3, 4, 1, 2])
    30          | 'Get max value' >>
    31          beam.CombineGlobally(lambda elements: max(elements or [None]))
    32          | beam.Map(print))
    33      # [END max_globally]
    34      if test:
    35        test(max_element)
    36  
    37  
    38  def max_per_key(test=None):
    39    # [START max_per_key]
    40    import apache_beam as beam
    41  
    42    with beam.Pipeline() as pipeline:
    43      elements_with_max_value_per_key = (
    44          pipeline
    45          | 'Create produce' >> beam.Create([
    46              ('🥕', 3),
    47              ('🥕', 2),
    48              ('🍆', 1),
    49              ('🍅', 4),
    50              ('🍅', 5),
    51              ('🍅', 3),
    52          ])
    53          | 'Get max value per key' >> beam.CombinePerKey(max)
    54          | beam.Map(print))
    55      # [END max_per_key]
    56      if test:
    57        test(elements_with_max_value_per_key)