Errors for Pkg.add("Gurobi")

[giualva]

I completely followed the directions to download and install gurobi but then then i run Pkg.add("Gurobi") it gives me an error message. Let me know what I should do!!

Stacktrace:
│  [1] error(::String) at ./error.jl:33
│  [2] top-level scope at /Users/giuliaalvarenga/.julia/packages/Gurobi/7YNJV/deps/build.jl:154
│  [3] include(::String) at ./client.jl:457
│  [4] top-level scope at none:5
│ in expression starting at /Users/giuliaalvarenga/.julia/packages/Gurobi/7YNJV/deps/build.jl:152
│ Unable to locate Gurobi installation. Running some common diagnostics.
│ 
│ Gurobi.jl only supports the following versions:
│ 
│  - gurobi90
│  - gurobi81
│  - gurobi80
│  - gurobi75
│  - gurobi70
│ 
│ Did you download and install one of these versions from gurobi.com?
│ 
│ 
│ Looking for a version of Gurobi in your path:
│ 
│ 
│ We couldn't find the `GUROBI_HOME` environment variable, but we
│ found this version of Gurobi on your path. Is this version one of
│ the supported versions listed above? If not, you should edit your
│ `PATH` to point to the correct version.

[odow]

Follow the installation instructions: https://github.com/jump-dev/Gurobi.jl#installation

You probably need something like

ENV["GUROBI_HOME"] = "/Library/gurobi902/mac64"
] add Gurobi
] build Gurobi