Upgrade to tf2

[FelixBenning]

An attempt to upgrade deepOBS tensorflow to 2.0

• [x] run tf_upgrade_v2 script on deepobs (cf. https://www.tensorflow.org/guide/upgrade), commit 5550bea

• [x] try to fix errors in reports.txt with replacements from tfa and apparent aliases from tf (e.g. tf.keras.layers.Flatten()(x) for tf.contrib.layers.flatten(x)) (commits dec400b ed0b72a cc5e9d8)

• [x] inspect warnings

• [x] run tf_upgrade_v2 script on tests - no issues (commit 3082d1f)

  output (0 issues that require attention)

  INFO line 33:4: Renamed 'tf.reset_default_graph' to 'tf.compat.v1.reset_default_graph'
  INFO line 48:9: Renamed 'tf.Session' to 'tf.compat.v1.Session'
  INFO line 25:4: Renamed 'tf.reset_default_graph' to 'tf.compat.v1.reset_default_graph'
  INFO line 40:9: Renamed 'tf.Session' to 'tf.compat.v1.Session'
  INFO line 69:8: Renamed 'tf.reset_default_graph' to 'tf.compat.v1.reset_default_graph'
  INFO line 96:21: Renamed 'tf.ConfigProto' to 'tf.compat.v1.ConfigProto'
  INFO line 98:21: Renamed 'tf.ConfigProto' to 'tf.compat.v1.ConfigProto'
  INFO line 100:18: Added keywords to args of function 'tf.reduce_mean'
  INFO line 101:13: Renamed 'tf.Session' to 'tf.compat.v1.Session'
  INFO line 102:21: Renamed 'tf.global_variables_initializer' to 'tf.compat.v1.global_variables_initializer'
  INFO line 153:63: Renamed 'tf.trainable_variables' to 'tf.compat.v1.trainable_variables'
  TensorFlow 2.0 Upgrade Script
  -----------------------------
  Converted 9 files
  Detected 0 issues that require attention
  --------------------------------------------------------------------------------
  
  
  Make sure to read the detailed log 'report_tests.txt'
  

  logfile

  ensorFlow 2.0 Upgrade Script
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  onverted 9 files
  etected 0 issues that require attention
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  etailed log follows:
  
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  nput tree: 'tests'
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  rocessing file 'tests\\check_image_datasets.py'
  outputting to 'tests\\check_image_datasets.py'
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  rocessing file 'tests\\check_image_datasets_old.py'
  outputting to 'tests\\check_image_datasets_old.py'
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  3:4: INFO: Renamed 'tf.reset_default_graph' to 'tf.compat.v1.reset_default_graph'
  8:9: INFO: Renamed 'tf.Session' to 'tf.compat.v1.Session'
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  rocessing file 'tests\\check_text_datasets.py'
  outputting to 'tests\\check_text_datasets.py'
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  5:4: INFO: Renamed 'tf.reset_default_graph' to 'tf.compat.v1.reset_default_graph'
  0:9: INFO: Renamed 'tf.Session' to 'tf.compat.v1.Session'
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  rocessing file 'tests\\test_testproblems.py'
  outputting to 'tests\\test_testproblems.py'
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  9:8: INFO: Renamed 'tf.reset_default_graph' to 'tf.compat.v1.reset_default_graph'
  6:21: INFO: Renamed 'tf.ConfigProto' to 'tf.compat.v1.ConfigProto'
  8:21: INFO: Renamed 'tf.ConfigProto' to 'tf.compat.v1.ConfigProto'
  00:18: INFO: Added keywords to args of function 'tf.reduce_mean'
  01:13: INFO: Renamed 'tf.Session' to 'tf.compat.v1.Session'
  02:21: INFO: Renamed 'tf.global_variables_initializer' to 'tf.compat.v1.global_variables_initializer'
  53:63: INFO: Renamed 'tf.trainable_variables' to 'tf.compat.v1.trainable_variables'
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  rocessing file 'tests\\__init__.py'
  outputting to 'tests\\__init__.py'
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  rocessing file 'tests\\pytorch\\testproblems\\test_quadratic_deep.py'
  outputting to 'tests\\pytorch\\testproblems\\test_quadratic_deep.py'
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  rocessing file 'tests\\utils\\utils_number_of_parameters.py'
  outputting to 'tests\\utils\\utils_number_of_parameters.py'
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  rocessing file 'tests\\utils\\utils_tests.py'
  outputting to 'tests\\utils\\utils_tests.py'
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  rocessing file 'tests\\utils\\__init__.py'
  outputting to 'tests\\utils\\__init__.py'
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• [ ] run unit tests