requirements: Upgrade pip to 18.0.
requirements: Upgrade pip to 18.0.

tommyip/zulip,dhcrzf/zulip,shubhamdhama/zulip,rishig/zulip,jackrzhang/zulip,punchagan/zulip,andersk/zulip,shubhamdhama/zulip,kou/zulip,zulip/zulip,punchagan/zulip,rishig/zulip,hackerkid/zulip,andersk/zulip,punchagan/zulip,tommyip/zulip,timabbott/zulip,dhcrzf/zulip,synicalsyntax/zulip,synicalsyntax/zulip,rht/zulip,timabbott/zulip,tommyip/zulip,tommyip/zulip,shubhamdhama/zulip,hackerkid/zulip,punchagan/zulip,brainwane/zulip,andersk/zulip,timabbott/zulip,punchagan/zulip,kou/zulip,tommyip/zulip,rishig/zulip,dhcrzf/zulip,synicalsyntax/zulip,hackerkid/zulip,eeshangarg/zulip,tommyip/zulip,timabbott/zulip,dhcrzf/zulip,showell/zulip,punchagan/zulip,rht/zulip,hackerkid/zulip,brainwane/zulip,synicalsyntax/zulip,eeshangarg/zulip,eeshangarg/zulip,eeshangarg/zulip,zulip/zulip,brainwane/zulip,showell/zulip,tommyip/zulip,synicalsyntax/zulip,rishig/zulip,hackerkid/zulip,showell/zulip,zulip/zulip,rht/zulip,eeshangarg/zulip,synicalsyntax/zulip,dhcrzf/zulip,shubhamdhama/zulip,rht/zulip,rishig/zulip,rht/zulip,andersk/zulip,dhcrzf/zulip,brainwane/zulip,timabbott/zulip,shubhamdhama/zulip,jackrzhang/zulip,hackerkid/zulip,brainwane/zulip,hackerkid/zulip,rht/zulip,dhcrzf/zulip,zulip/zulip,kou/zulip,brainwane/zulip,jackrzhang/zulip,showell/zulip,rishig/zulip,rishig/zulip,zulip/zulip,jackrzhang/zulip,kou/zulip,eeshangarg/zulip,shubhamdhama/zulip,eeshangarg/zulip,punchagan/zulip,zulip/zulip,kou/zulip,andersk/zulip,jackrzhang/zulip,zulip/zulip,andersk/zulip,showell/zulip,kou/zulip,jackrzhang/zulip,kou/zulip,showell/zulip,showell/zulip,jackrzhang/zulip,shubhamdhama/zulip,timabbott/zulip,brainwane/zulip,rht/zulip,synicalsyntax/zulip,andersk/zulip,timabbott/zulip