code: def remove_connection(self, alias):
          
          errors = 0
          for d in (self._conns, self._kwargs):
              try:
                  del d[alias]
              except KeyError:
                  errors += 1
  
          if errors == 2:
              raise KeyError('There is no connection with alias %r.' % alias)
docs: Remove connection from the registry. Raises ``KeyError`` if connection
          wasn't found.