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

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())