Generate test data, unique ids, passwords, vouchers or other randomized textual data very quickly using a template language. The template language is superficially similar to regular expressions but instead of defining how to match or capture strings, it defines how to generate randomized strings. A very simple invocation to produce a random string with word characters of 30 characters length:

from strgen import StringGenerator as SG

Generate 50000 unique secure tokens, each 32 characters:

secure_tokens = SG("[\p\w]{32}").render_set(50000)


pip install StringGenerator

The current package requires Python 3.6 or higher. Use version 0.3.4 or earlier if you want to use Python 2.7 or an earlier Python 3 version.

The purpose of this module is to save the Python developer from having to write verbose code around the same pattern every time to generate passwords, keys, tokens, test data, etc. of this sort:

my_secret_key = ''.join(random.choice(string.ascii_uppercase + string.digits) for x in range(30))

that is:

  1. Hard to read even at this simplistic level.

  2. Hard to safely change quickly. Even modest additions to the requirements need unreasonably verbose solutions.

  3. Doesn’t use safe encryption standards.

  4. Doesn’t provide the implied minimal guarantees of character occurance.

  5. Hard to track back to requirements (“must be between x and y in length and have characters from sets Q, R and S”).

The template uses short forms similar to those of regular expressions. An example template for generating the same secret key as above:


will generate something like the following:


Changing the character specification is a matter of adding two characters.

Guarantee at least two “special” characters in a string:


You can also generate useful test data, like fake emails with plenty of variation:


Testing and Developing

For running the unit tests or making changes, you might want to try:

python -m venv .venv && source .venv/bin/activate && pip install --upgrade pip && pip install -r requirements.txt

Hypothesis is used in some unit tests


Released under the BSD license.

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