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Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

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Dictionaries & sets easy

How to Parse Query String to Dict with Duplicate Keys in Python

Convert a URL query string into a Python dictionary, merging duplicate keys into lists while keeping single values as scalars.

query-string dict url-parsing
Python 
from urllib.parse import parse_qs


def parse_query_to_dict(query_string):
    parsed = parse_qs(query_string, keep_blank_values=True)
    return {key: values if len(values) > 1 else values[0] for key, values in parsed.items()}


if __name__ == "__main__":
    query = "name=John&name=Jane&age=30&city=&city=Paris&empty…
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