import re

strings = [
    "{tvg-id: , tvg-name: A beautiful Day - 2016, tvg-logo: https://i...content-available-to-author-only...b.org/t/p/w600_and_h900_bestv2/hZgsmIYUAtdUOUFKROq6rNyWXVa.jpg, group-title: 2017-16-15 Germany Cinema}",
    "{tvg-id: , tvg-name: Antonio, ihm schmeckt's nicht! (2016), tvg-logo: https://i...content-available-to-author-only...b.org/t/p/w600_and_h900_bestv2/dyLfGb1mF2PUd0Rz5kqKiYtQl3r.jpg, group-title: 2017-16-15 Germany Cinema}"
    ]

def convert(example):
    pattern = r"([^\s:,{}]+):\s*([^,{}]*)"
    dct = {}
    if example.endswith and example.startswith:
        for t in re.findall(pattern, example):
            if t[1].strip():
                dct[t[0]] = t[1]
            else:
                dct[t[0]] = None
    return dct

for s in strings:
    print(convert(s))