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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 -->

<!--- Paste example playbooks or commands between quotes below -->
```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

```

- name: authenticate with a Vault app role
  debug:
      msg: "{{ lookup('hashi_vault', 'secret=secret/hello:value auth_method=approle role_id=myroleid secret_id=mysecretid url=http://myvault:8200')}}"
- name: Return all secrets from a path in a namespace
  debug:
    msg: "{{ lookup('hashi_vault', 'secret=secret/hello token=c975b780-d1be-8016-866b-01d0f9b688a5 url=http://myvault:8200 namespace=teama/admins')}}"
# to work with kv v2 (vault api - for kv v2 -  GET method requires that PATH should be "secret/data/:path")
- name: Return all kv v2 secrets from a path
  debug:
    msg: "{{ lookup('hashi_vault', 'secret=secret/data/hello token=my_vault_token url=http://myvault_url:8200') }}"
"""
RETURN = """
_raw:
  description:
    - secrets(s) requested
"""
import os
from ansible.errors import AnsibleError
from ansible.module_utils.parsing.convert_bool import boolean
from ansible.plugins.lookup import LookupBase
HAS_HVAC = False
try:
    import hvac
    HAS_HVAC = True
except ImportError:
    HAS_HVAC = False
ANSIBLE_HASHI_VAULT_ADDR = 'http://127.0.0.1:8200'
if os.getenv('VAULT_ADDR') is not None:
    ANSIBLE_HASHI_VAULT_ADDR = os.environ['VAULT_ADDR']
class HashiVault: