old_contents: """
  The MIT License (MIT)
  
  Copyright (c) 2017 Stefan Graupner
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
  """
  
  from glob import glob
  from importlib import import_module
  
  from core.utils import camelize_snake, get_base_classes_from_instance
  
  class Pool:
      """
          Collect all extra checks and provide them in a pool
          for easy use across validation worker threads.^
      """
  
      def __init__(self):
          self.checks = {}
          check_files = glob('extra/check_*.py')
          for check_file in check_files:
              class_instance = self.load_class_from_file(check_file)
  
              if not self.is_check(class_instance):
                  continue
  
              self.add_check(class_instance)
  
  
      def load_class_from_file(self, filename):
          module_name, class_name = self.extract_loading_info(filename)
  
          module = import_module(module_name)
          class_definition = getattr(module, class_name)
          class_instance = class_definition()
  
          return class_instance
  
      def extract_loading_info(self, filename):
          module_name = filename.split('.py')[0].replace('/', '.')
          class_name = camelize_snake(module_name.split('.')[1])
  
          return (module_name, class_name)
  
      def is_check(self, class_instance):
          return 'core.check.Check' in get_base_classes_from_instance(class_instance)
  
      def add_check(self, class_instance):
          entity = class_instance.evaluates_entity_type()
          if not entity in self.checks.keys() or type(self.checks[entity]) is not 'list':
              self.checks[entity] = []
  
          self.checks[entity].append(class_instance)
  
      def get_checks_for_type(self, type : str):
          return self.checks[type.lower()]
new_contents: """
  The MIT License (MIT)
  
  Copyright (c) 2017 Stefan Graupner
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
  """
  
  from glob import glob
  from importlib import import_module
  
  from core.utils import camelize_snake, get_base_classes_from_instance
  
  class Pool:
      """
          Collect all extra checks and provide them in a pool
          for easy use across validation worker threads.^
      """
  
      def __init__(self):
          self.checks = {}
          check_files = glob('extra/check_*.py')
          for check_file in check_files:
              class_instance = self.load_class_from_file(check_file)
  
              if not self.is_check(class_instance):
                  continue
  
              self.add_check(class_instance)
  
  
      def load_class_from_file(self, filename):
          module_name, class_name = self.extract_loading_info(filename)
  
          module = import_module(module_name)
          class_definition = getattr(module, class_name)
          class_instance = class_definition()
  
          return class_instance
  
      def extract_loading_info(self, filename):
          module_name = filename.split('.py')[0].replace('/', '.')
          class_name = camelize_snake(module_name.split('.')[1])
  
          return (module_name, class_name)
  
      def is_check(self, class_instance):
          return 'core.check.Check' in get_base_classes_from_instance(class_instance)
  
      def add_check(self, class_instance):
          entity = class_instance.evaluates_entity_type()
          if not entity in self.checks.keys() or type(self.checks[entity]) is not 'list':
              self.checks[entity] = []
  
          self.checks[entity].append(class_instance)
  
      def get_checks_for_type(self, type : str):
          type = type.lower()
  
          if type in self.checks.keys():
              return self.checks[type]
  
          return []
subject: Make sure the entity has extra checks