我很难安装 localstack。这是在刚刚重新格式化的 ubuntu 电脑上。我不断收到此错误：
(test which virtualenv || pip install --user virtualenv) &&
(test -e .venv || virtualenv .venv) &&
(test ! -e requirements.txt || (. .venv/bin/activate; pip -q install -r requirements.txt) &&
. .venv/bin/activate; PYTHONPATH=. exec python localstack/services/install.py testlibs)
Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f13119c7910>: Failed to establish a new connection: [Errno -3] Try again',)': /simple/airspeed/
Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f13119c7b90>: Failed to establish a new connection: [Errno -3] Try again',)': /simple/airspeed/
Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f13119c7cd0>: Failed to establish a new connection: [Errno -3] Try again',)': /simple/airspeed/
Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f13119c7e10>: Failed to establish a new connection: [Errno -3] Try again',)': /simple/airspeed/
Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f13119c7f50>: Failed to establish a new connection: [Errno -3] Try again',)': /simple/airspeed/
Could not find a version that satisfies the requirement airspeed==0.5.5.dev20160812 (from -r requirements.txt (line 4)) (from versions: )
No matching distribution found for airspeed==0.5.5.dev20160812 (from -r requirements.txt (line 4))
有人对此有解决方案吗？