code: def unregister(self, provider):
          '''Unregister an existing data provider.
  
          *provider* must be an instance of DataProvider.
          If provider name is already available, it will be replaced.
          '''
          if isinstance(provider, type):
              provider = provider()
          if isinstance(provider, DataProvider):
              provider = provider.code
          return self.pop(str(provider).upper(), Nonef unregister(self, provider):
          '''Unregister an existing data provider.
  
          *provider* must be an instance of DataProvider.
          If provider name is already available, it will be replaced.
          '''
          if isinstance(provider, type):
              provider = provider()
          if isinstance(provider, DataProvider):
              provider = provider.code
          return self.pop(str(provider).upper(), None)
docs: Unregister an existing data provider.
  
          *provider* must be an instance of DataProvider.
          If provider name is already available, it will be replaced.