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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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'''parse our password data format into password and salt
    :arg content: The data read from the file
    :returns: password and salt
    '''
    password = content
    salt = None
    salt_slug = u' salt='
    try:
        sep = content.rindex(salt_slug)
    except ValueError:
        
        pass
    else:
        salt = password[sep + len(salt_slug):]
        password = content[:sep]
    return password, salt
def _format_content(password, salt, encrypt=None):