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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
In the user module, in the docs for the password field, there is a link to instructions on how to create a password hash for the module to consume. Said link is broken, and gives a 404.


Cf. [the corresponding line in the user module](https://github.com/ansible/ansible/blob/2b0cd2c13f2021f839600d601f75dea2c0343ed1/lib/ansible/modules/user.py#L92)


> HINT: Did you know the documentation has an "Edit on GitHub" link on every page ?

this one doesn't, or i just could not find it : /

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
user module
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
latest
```

if self.groups is None:
            return None
        info = self.user_info()
        groups = set(x.strip() for x in self.groups.split(',') if x)
        for g in groups.copy():
            if not self.group_exists(g):
                self.module.fail_json(msg="Group %s does not exist" % (g))
            if info and remove_existing and self.group_info(g)[2] == info[3]:
                groups.remove(g)
        return groups
    def user_group_membership(self, exclude_primary=True):
        ''' Return a list of groups the user belongs to '''
        groups = []
        info = self.get_pwd_info()
        for group in grp.getgrall():
            if self.name in group.gr_mem:
                
                if not exclude_primary:
                    groups.append(group[0])
                else:
                    if info[3] != group.gr_gid:
                        groups.append(group[0])
        return groups
    def user_exists(self):