class_docstr: Model formula
  
  Allows to describe a model with multiple formulas. The first formula describes the response
  variable and its predictors. The following formulas describe predictors for other parameters
  of the likelihood function, allowing distributional models.
  
  Parameters
  ----------
  formula : str
      A model description written using the formula syntax from the ``formulae`` library.
  *additionals : str
      Additional formulas that describe the
code: def __str__(self):
      formulas = [self.main] + list(self.additionals)
      middle = ", ".join(formulas)
      return f"Formula({middle})"
  
file_path: bambi/bambi/formula.py
imports: import warnings
  from typing import Sequence
  import formulae
label_desc: Use image node_id 5 for calling the Formula obj's underlying member method code with example usage: obj.__str__() and returns: str, middle, str