class_docstr: A FA class, inherited from Optimizer.
  
  This is the designed class to define FA-related
  variables and methods.
  
  References:
      X.-S. Yang. Firefly algorithms for multimodal optimization.
      International symposium on stochastic algorithms (2009).
class_docstr_tok: ["A","FA","class",",","inherited","from","Optimizer",".","This","is","the","designed","class","to","define","FA-related","variables","and","methods",".","References",":","X.-S.","Yang",".","Firefly","algorithms","for","multimodal","optimization",".","International","symposium","on","stochastic","algorithms","(","2009",")","."]
code: def alpha(self, alpha: float) -> None:
      if not isinstance(alpha, (float, int)):
          raise e.TypeError("`alpha` should be a float or integer")
      if alpha < 0:
          raise e.ValueError("`alpha` should be >= 0")
  
      self._alpha = alpha
  
file_path: opytimizer/opytimizer/optimizers/swarm/fa.py
imports: import copy
  from typing import Any, Dict, Optional
  import numpy
  import opytimizer.math.general
  import opytimizer.math.random
  import opytimizer.utils.exception
  from opytimizer.core import Optimizer
  from opytimizer.core.space import Space
  from opytimizer.utils import logging
label_desc: Use image node_id 3 for calling the FA obj's underlying member method code with example usage: obj.alpha(alpha) without return types