code: def truth(val, context):
      
      try:
          0 + val
      except TypeError:
          lower_val = val.lower()
  
          if lower_val in TRUE:
              return True
          elif lower_val in FALSE:
              return False
          else:
              raise FilterError("Bad boolean value %r in %r (expected one of '%s', or '%s')" % (
                  val, context, "' '".join(TRUE), "' '".join(FALSE)
              ))
      else:
          return bool(val)
docs: Convert truth value in "val" to a boolean.