class_docstr: AbstractSolver base class for mystic optimizers.
      
class_docstr_tok: ["AbstractSolver","base","class","for","mystic","optimizers","."]
docstr: enable workflow interrupt handler while solver is running
code: def enable_signal_handler(self):  # , callback='*'):
      """enable workflow interrupt handler while solver is running"""
      """ #XXX: disabled, as would add state to solver
  input::
      - if a callback function is provided, generate a new handler with
        the given callback.  If callback is None, do not use a callback.
        If callback is not provided, just turn on the existing handler.
  """
      ## always _generate handler on first call
      # if (self.signal_handler is None) and callback == '*':
      #    callback = None
      ## when a new callback is given, generate a new handler
      # if callback != '*':
      #    self._generateHandler(callback)
      self._handle_sigint = True
  
imports: import random
  import numpy
  from numpy import inf, shape, asarray, absolute, asfarray, seterr
  from mystic.tools import wrap_function, wrap_nested, wrap_reducer
  from mystic.tools import wrap_bounds, wrap_penalty, reduced
  from klepto import isvalid, validate
  from collections.abc import Callable
label_desc: Use image node_id 25 for calling the AbstractSolver obj's underlying member method code with example usage: obj.enable_signal_handler() without return types