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##### SUMMARY

Invoking the 'bitbucket_access_key' of ansible 2.8 installed with pip 19.1 on python 2.7 (Ubuntu 14.04...) gives the following error.

```
 line 114, in <module>\n    _ansiballz_main()\n  File \"/home/ubuntu/.ansible/tmp/ansible-tmp-1561635678.17-267746543539506/AnsiballZ_bitbucket_access_key.py\", line 106, in _ansiballz_main\n    invoke_module(zipped_mod, temp_path, ANSIBALLZ_PARAMS)\n  File \"/home/ubuntu/.ansible/tmp/ansible-tmp-1561635678.17-267746543539506/AnsiballZ_bitbucket_access_key.py\", line 49, in invoke_module\n    imp.load_module('__main__', mod, module, MOD_DESC)\n  File \"/tmp/ansible_bitbucket_access_key_payload_yyexZQ/__main__.py\", line 285, in <module>\n  File \"/tmp/ansible_bitbucket_access_key_payload_yyexZQ/__main__.py\", line 256, in main\n  File \"/tmp/ansible_bitbucket_access_key_payload_yyexZQ/__main__.py\", line 169, in get_existing_deploy_key\nTypeError: list object is not an iterator\n", "module_stdout": "", "msg": "MODULE FAILURE\nSee stdout/stderr for the exact error", "rc": 1}
```


##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
bitbucket_access_key module

##### ANSIBLE VERSION
```
/usr/local/lib/python2.7/dist-packages/cryptography/hazmat/primitives/constant_time.py:26: CryptographyDeprecationWarning: Support for your Python version is deprecated. The next version of cryptography will remove support. Please upgrade to a release (2.7.7+) that supports hmac.compare_digest as soon as possible.
  utils.PersistentlyDeprecated2018,
ansible 2.8.1
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/ubuntu/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /home/ubuntu/.local/lib/python2.7/site-packages/ansible
  executable location = /usr/local/bin/ansible
  python version = 2.7.6 (default, Nov 13 2018, 12:45:42) [GCC 4.8.4]

```

##### Patch
The following patch fixes the issue:

```
--- bitbucket_access_key.py.orig        2019-06-27 12:17:18.168641126 +0000
+++ bitbucket_access_key.py     2019-06-27 12:16:59.664723635 +0000
@@ -166,7 +166,7 @@
         if info['status'] != 200:
             module.fail_json(msg='Failed to retrieve the list of deploy keys: {0}'.format(info))

-        res = next(filter(lambda v: v['label'] == module.params['label'], content['values']), None)
+        res = next(iter(filter(lambda v: v['label'] == module.params['label'], content['values'])), None)

         if res is not None:
             return res
```

bitbucket_access_key:
    repository: 'bitbucket-repo'
    username: bitbucket_username
    key: '{{lookup("file", "bitbucket.pub") }}'
    label: 'Bitbucket'
    state: present
- name: Delete access key
  bitbucket_access_key:
    repository: bitbucket-repo
    username: bitbucket_username
    label: Bitbucket
    state: absent
'''
RETURN = r''' # '''
from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.source_control.bitbucket import BitbucketHelper
error_messages = {
    'required_key': '`key` is required when the `state` is `present`',
    'required_permission': 'OAuth consumer `client_id` should have permissions to read and administrate the repository',
    'invalid_username_or_repo': 'Invalid `repository` or `username`',
    'invalid_key': 'Invalid SSH key or key is already in use',
}
BITBUCKET_API_ENDPOINTS = {
    'deploy-key-list': '%s/2.0/repositories/{username}/{repo_slug}/deploy-keys/' % BitbucketHelper.BITBUCKET_API_URL,
    'deploy-key-detail': '%s/2.0/repositories/{username}/{repo_slug}/deploy-keys/{key_id}' % BitbucketHelper.BITBUCKET_API_URL,
}
def get_existing_deploy_key(module, bitbucket):
    """
    Search for an existing deploy key on Bitbucket
    with the label specified in module param `label`