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##### SUMMARY
<!--- Explain the problem briefly below -->
The env lookup plugin fails with an error when the environment variable value contains an UTF8 character.
The problem exists since Ansible 2.9 and only with Python 2.7 

##### ISSUE TYPE
- Bug Report

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

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.1
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/admin/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/dist-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.15+ (default, Oct  7 2019, 17:39:04) [GCC 7.4.0]
```

##### 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. -->

```
Ubuntu 18.04.3 LTS
```

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

<!--- Paste example playbooks or commands between quotes below -->
```shell
TESTENVVAR=éáúőúöüó ansible all -i localhost, -m debug -a msg="{{ lookup('env','TESTENVVAR') }}"
```

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

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

```
localhost | SUCCESS => {
    "msg": "éáúőúöüó"
}
```
##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
localhost | FAILED! => {
    "msg": "the field 'args' has an invalid value ({u'msg': u\"{{ lookup('env','TESTENVVAR') }}\"}), and could not be converted to an dict.The error was: 'ascii' codec can't decode byte 0xc3 in position 0: ordinal not in range(128)"
}
```

def run(self, terms, variables, **kwargs):
        ret = []
        for term in terms:
            var = term.split()[0]
            ret.append(os.getenv(var, ''))
        return ret