Python how convert single quotes to double quotes to format as json string

Question

I have a file where on each line I have text like this (representing cast of a film):

[{'cast_id': 23, 'character': "Roger 'Verbal' Kint", 'credit_id': '52fe4260c3a36847f8019af7', 'gender': 2, 'id': 1979, 'name': 'Kevin Spacey', 'order': 5, 'profile_path': '/x7wF050iuCASefLLG75s2uDPFUu.jpg'}, {'cast_id': 27, 'character': 'Edie's Finneran', 'credit_id': '52fe4260c3a36847f8019b07', 'gender': 1, 'id': 2179, 'name': 'Suzy Amis', 'order': 6, 'profile_path': '/b1pjkncyLuBtMUmqD1MztD2SG80.jpg'}]

I need to convert it in a valid json string, thus converting only the necessary single quotes to double quotes (e.g. the single quotes around word Verbal must not be converted, eventual apostrophes in the text also should not be converted).

I am using python 3.x. I need to find a regular expression which will convert only the right single quotes to double quotes, thus the whole text resulting in a valid json string. Any idea?