code: def sample_ball(p0, std, size=1):
      """
      Produce a ball of walkers around an initial parameter value.
  
      :param p0: The initial parameter value.
      :param std: The axis-aligned standard deviation.
      :param size: The number of samples to produce.
  
      """
      assert len(p0) == len(std)
      return np.vstack(
          [
              p0 + std * np.random.normal(size=len(p0))
              for i in range(size)
          ]
      )
  
imports: import warnings
  from functools import wraps
  import numpy
label_desc: Use image node_id 3 for calling a global function with example usage: sample_ball(p0, std, size) and returns: np