pod install fail

[hejunbinlan]

pod install
Analyzing dependencies
Downloading dependencies
Installing AFNetworking (2.5.4)
Installing AFOnoResponseSerializer (1.0.0)

[!] Error installing AFOnoResponseSerializer
[!] /usr/bin/git clone https://github.com/AFNetworking/AFOnoResponseSerializer.git /var/folders/sy/k4w3rd3s0fjckn2t2r1h541c0000gn/T/d20150730-15510-bf2c87 --single-branch --depth 1 --branch 1.0.0

Cloning into '/var/folders/sy/k4w3rd3s0fjckn2t2r1h541c0000gn/T/d20150730-15510-bf2c87'...

fatal: unable to access 'https://github.com/AFNetworking/AFOnoResponseSerializer.git/': Proxy CONNECT aborted