docstr: This function links the user's choice of transformation with the associated numpy function
code: def transform_define(transform):
      """
      This function links the user's choice of transformation with the associated numpy function
      """
      if transform == "tanh":
          return np.tanh
      elif transform == "exp":
          return np.exp
      elif transform == "logit":
          return Family.ilogit
      elif transform is None:
          return np.array
      else:
          return None
  
file_path: pyflux/pyflux/families/family.py
imports: import numpy
label_desc: Use image node_id 4 for calling the Family obj's underlying member method code with example usage: obj.transform_define(transform) and returns: np, np, Family, np, None