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##### SUMMARY
<!--- Explain the problem briefly below -->
Hi, i am trying to read a secret from the following path
        secret: "{{ lookup('hashi_vault', 'namespace={{NAMESPACE}} secret={{ BRAND }}/{{ ENVIRONMENT }}/secrets/placeholder:foo url={{ VAULT_ADDR }} auth_method={{ VAULT_AUTH_METHOD }} role_id={{ VAULT_ROLE_ID }} secret_id={{ VAULT_SECRET_ID }}')}}"

but this fails with no secret found at location. 
we are using enterprise and this uses the KV engine

vault kv get {{ BRAND }}/{{ ENVIRONMENT }}/secrets/placeholder:foo


##### ISSUE TYPE
- Bug Report
unable to read from kv data store

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
hashi_vault

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
2.8
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

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```yaml

```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->


##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below

```

def __init__(self, **kwargs):
        self.url = kwargs.get('url', ANSIBLE_HASHI_VAULT_ADDR)
        self.namespace = kwargs.get('namespace', None)
        self.avail_auth_method = ['approle', 'userpass', 'ldap']
        
        s = kwargs.get('secret')
        if s is None:
            raise AnsibleError("No secret specified for hashi_vault lookup")
        s_f = s.rsplit(':', 1)
        self.secret = s_f[0]
        if len(s_f) >= 2:
            self.secret_field = s_f[1]
        else:
            self.secret_field = ''
        self.verify = self.boolean_or_cacert(kwargs.get('validate_certs', True), kwargs.get('cacert', ''))
        
        
        
        #
        
        #
        self.auth_method = kwargs.get('auth_method', os.environ.get('VAULT_AUTH_METHOD'))
        self.verify = self.boolean_or_cacert(kwargs.get('validate_certs', True), kwargs.get('cacert', ''))