code: def positive(x):
      """Return zero if value is negative"""
      if x is None:
          return
      if isinstance(x, str):
          return x
      if x < 0:
          return 0
      return x
  
imports: from decimal import Decimal
label_desc: Use image node_id 1 for calling a global function with example usage: positive(x) and returns: x, x, int