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##### SUMMARY
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https://docs.ansible.com/ansible/latest/collections/ansible/builtin/password_lookup.html :

> Define comma separated list of names that compose a custom character set in the generated passwords.
> They can be either parts of Python's string module attributes (ascii_letters,digits, etc) or are used literally ( :, -).

I suggest to list all possible names or at least add a link to python string module documentation: https://docs.python.org/3/library/string.html

Now you have to search for the relevant python documentation yourself.

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##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
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ansible.builtin.password

##### ADDITIONAL INFORMATION
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which simplifies password management in C("host_vars") variables.'
      - A special case is using /dev/null as a path. The password lookup will generate a new random password each time,
        but will not write it to /dev/null. This can be used when you need a password without storing it on the controller.
    options:
      _terms:
         description:
           - path to the file that stores/will store the passwords
         required: True
      encrypt:
        description:
           - Which hash scheme to encrypt the returning password, should be one hash scheme from C(passlib.hash; md5_crypt, bcrypt, sha256_crypt, sha512_crypt)
           - If not provided, the password will be returned in plain text.
           - Note that the password is always stored as plain text, only the returning password is encrypted.
           - Encrypt also forces saving the salt value for idempotence.
           - Note that before 2.6 this option was incorrectly labeled as a boolean for a long time.
      chars:
        version_added: "1.4"
        description:
          - Define comma separated list of names that compose a custom character set in the generated passwords.
          - 'By default generated passwords contain a random mix of upper and lowercase ASCII letters, the numbers 0-9 and punctuation (". , : - _").'
          - "They can be either parts of Python's string module attributes (ascii_letters,digits, etc) or are used literally ( :, -)."
          - "Other valid values include 'ascii_lowercase', 'ascii_uppercase', 'digits', 'hexdigits', 'octdigits', 'printable', 'punctuation' and 'whitespace'."
          - Be aware that Python's 'hexdigits' includes lower and upper case version of a-f, so it is not a good choice as it doubles
            the chances of those values for systems that won't distinguish case, distorting the expected entropy.
          - "To enter comma use two commas ',,' somewhere - preferably at the end. Quotes and double quotes are not supported."
        type: string
      length:
        description: The length of the generated password.
        default: 20
        type: integer