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Python 3.6: How to expand f-string literals read from a file vs inline statement


My original post reformatted for text mode:

Looking for advice on how to expand f-string literal strings whose values I'm reading from a configuration file vs hard coding into 
my script as statements. I'm using f-strings as a very simple template language.

I'm currently using the following technique to expand these f-strings. Is there a better way?

Bonus if anyone has suggestions on how my expand() function can access the locals() value of the caller so this parameter doesn't have to be passed in explicitly.

def expand(expression, values):
   """Expand expression using passed in locals()"""
   triple_quote = "'" * 3
   expression = dedent(expression)
   return eval(f'f{triple_quote}{expression}{triple_quote}', None, values)

product_name = 'Bike ABC'
product_sku = '123456'
product_price = 299.95
discount = 0.85

# read in product description template 
# product_description_template might look like: {product_sku} : {product_name}: ${product_price * discount}
product_description_template = config('product_description_template')

# expand the {expressions} in product_description_template using my locals()
product_description = expand(product_description_template, locals())