## Description of the issue

The docker-compose is not working.

See also: https://github.com/docker/compose/issues/6915

## Context information (for bug reports)

**Output of `docker-compose version`**
```
Traceback (most recent call last):
File "/usr/bin/docker-compose", line 6, in <module>
from pkg_resources import load_entry_point
File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3241, in <module>
@_call_aside
File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3225, in _call_aside
f(*args, **kwargs)
File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3254, in _initialize_master_working_set
working_set = WorkingSet._build_master()
File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 583, in _build_master
ws.require(__requires__)
File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 900, in require
needed = self.resolve(parse_requirements(requirements))
File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 786, in resolve
raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'dockerpty>=0.4.1' distribution was not found and is required by docker-compose
```

**Output of `docker version`**
```
Client:
Version: 19.03.1-ce
API version: 1.40
Go version: go1.12.7
Git commit: 74b1e89e8a
Built: Sat Jul 27 21:08:50 2019
OS/Arch: linux/amd64
Experimental: false

Server:
Engine:
Version: 19.03.1-ce
API version: 1.40 (minimum version 1.12)
Go version: go1.12.7
Git commit: 74b1e89e8a
Built: Sat Jul 27 21:08:28 2019
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: v1.2.7.m
GitCommit: 85f6aa58b8a3170aec9824568f7a31832878b603.m
runc:
Version: 1.0.0-rc8
GitCommit: 425e105d5a03fabd737a126ad93d62a9eeede87f
docker-init:
Version: 0.18.0
GitCommit: fec3683
```

**Output of `docker-compose config`**

Same stacktrace as above.

## Steps to reproduce the issue

1. `sudo pacman -S docker-compose`
2. `docker-compose --version`

### Observed result

`docker-compose --version` command fails after installed docker-compose.

### Expected result

`docker-compose --version` should print the version of docker-compose.

### Stacktrace / full error message

See above.

## Additional information

**lsb_release -a**

```
LSB Version: n/a
Distributor ID: ManjaroLinux
Description: Manjaro Linux
Release: 18.0.4
Codename: Illyria
```

Docker-compose has been installed with pacman, [from the community repository](https://www.archlinux.org/packages/community/any/docker-compose/).

Note that I did not added docker group to sudoers and I use the docker command with `sudo docker`, but I get the same result with `sudo docker-compose --version`.