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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
The contains attribute of the find_module has type "string" but is described as "one or more regex patterns". Given that a string can only be one regex pattern (albeit with alternations in it to match against multiple patterns) it is deceptively easy to misread this and try to specify a list of strings as the value of the contains attribute.

Granted, Ansible warns about this when running, but it would be even better to prevent the mistake in the first place.

<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->
I would edit the documentation myself, but I don't actually know what the intended semantics for this are. Is the command meant to take a list of regexes? If so, the bug is that it doesn't. If it's only meant to take a single regex, the bug is in the description in the documentation!

##### 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 -->
find_module

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.4
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_VAULT_PASSWORD_FILE(env: ANSIBLE_VAULT_PASSWORD_FILE) = /home/kqr/.vaultpass
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. OS version, browser, etc. -->
All (documentation published on the web)

##### ADDITIONAL INFORMATION
<!--- Describe how this improves the documentation, e.g. before/after situation or screenshots -->

<!--- HINT: You can paste gist.github.com links for larger files -->

'''filter using glob patterns'''
    if patterns is None and excludes is None:
        return True
    if use_regex:
        if patterns and excludes is None:
            for p in patterns:
                r = re.compile(p)
                if r.match(f):
                    return True
        elif patterns and excludes:
            for p in patterns: