code: def _validate_incompatibilities(self, incompatibles):
          
          for element in incompatibles:
              if type(element) is list:
                  i = [a for a in element if self._get_parameter(a)]
                  if len(i) > 1:
                      raise ValueError("Options {} are incompatible".format(" and ".join(i)))
              elif type(incompatibles) is dict:
                  if self._get_parameter(element):
                      for b in incompatibles[element]:
                          if self._get_parameter(b):
                              raise ValueError("Options %s and %s are incompatible."
                                               % (element, b))
              else:
                  for a in element:
                      if self._get_parameter(a):
                          for b in incompatibles[a]:
                              if self._get_parameter(b):
                                  raise ValueError("Options %s and %s are incompatible."
                                                   % (a, b))
docs: Used by the bowtie _validate method (PRIVATE).