name: get_variable
returns: any
description: |
  This function can be used to dynamically obtain a variable. `res =
  get_variable(varname, fallback)` takes the value of `varname` (which
  must be a string) and stores the variable of that name into `res`. If
  the variable does not exist, the variable `fallback` is stored to
  `res`instead. If a fallback is not specified, then attempting to read
  a non-existing variable will cause a fatal error.

posargs:
  variable_name:
    type: str
    description: Name of the variable to get

optargs:
  default:
    type: any
    description: Fallback value to return when the variable does not exist