class_docstr: A String Formatter that allows evaluation of simple expressions.
  
  Note that this version interprets a `:`  as specifying a format string (as per
  standard string formatting), so if slicing is required, you must explicitly
  create a slice.
  
  This is to be used in templating cases, such as the parallel batch
  script templates, where simple arithmetic on arguments is useful.
  
  Examples
  --------
  ::
  
      In [1]: f = EvalFormatter()
      In [2]: f.format('{n//4}', n=8)
      Out[2]: '2'
  
      In [3]: f.format("{greeting[slice(2,4)]}", greeting="Hello")
      Out[3]: 'll'
class_docstr_tok: ["A","String","Formatter","that","allows","evaluation","of","simple","expressions",".","Note","that","this","version","interprets","a","`",":","`","as","specifying","a","format","string","(","as","per","standard","string","formatting",")",",","so","if","slicing","is","required",",","you","must","explicitly","create","a","slice",".","This","is","to","be","used","in","templating","cases",",","such","as","the","parallel","batch","script","templates",",","where","simple","arithmetic","on","arguments","is","useful",".","Examples","--","--","--","--",":",":","In","[","1","]",":","f","=","EvalFormatter","(",")","In","[","2","]",":","f.format","(","'","{","n\/\/4","}","'",",","n=8",")","Out","[","2","]",":","'","2'","In","[","3","]",":","f.format","(","``","{","greeting","[","slice","(","2,4",")","]","}","''",",","greeting=","''","Hello","''",")","Out","[","3","]",":","'ll","'"]
code: def get_field(self, name, args, kwargs):
      v = eval(name, kwargs)
      return v, name
  
imports: import os
  import re
  import string
  import sys
  import textwrap
  import warnings
  from string import Formatter
  from pathlib import Path
  from typing import List, Union, Optional, Dict, Tuple
label_desc: Use image node_id 1 for calling the EvalFormatter obj's underlying member method code with example usage: obj.get_field(name, args, kwargs) and returns: v,  name