Error importing cv2 in julia0.7

```
julia> @pyimport cv2
ERROR: BoundsError: attempt to access ""
at index [1]
Stacktrace:
[1] checkbounds at ./strings/basic.jl:193 [inlined]
[2] codeunit at ./strings/string.jl:87 [inlined]
[3] getindex at ./strings/string.jl:206 [inlined]
[4] (::getfield(PyCall, Symbol("##77#81")))(::Tuple{String,PyObject}) at /home/ayush99/.julia/dev/PyCall/src/PyCall.jl:336
[5] iterate(::Base.Iterators.Filter{getfield(PyCall, Symbol("##77#81")),Array{Tuple{AbstractString,PyObject},1}}) at ./iterators.jl:434
[6] iterate at ./generator.jl:44 [inlined]
[7] grow_to!(::Array{Symbol,1}, ::Base.Generator{Base.Iterators.Filter{getfield(PyCall, Symbol("##77#81")),Array{Tuple{AbstractString,PyObject},1}},getfield(PyCall, Symbol("##76#80"))}) at ./array.jl:674
[8] collect(::Base.Generator{Base.Iterators.Filter{getfield(PyCall, Symbol("##77#81")),Array{Tuple{AbstractString,PyObject},1}},getfield(PyCall, Symbol("##76#80"))}) at ./array.jl:617
[9] pywrap(::PyObject, ::Symbol) at /home/ayush99/.julia/dev/PyCall/src/PyCall.jl:336
[10] pywrap(::PyObject) at /home/ayush99/.julia/dev/PyCall/src/PyCall.jl:328
[11] top-level scope at /home/ayush99/.julia/dev/PyCall/src/PyCall.jl:526
```

Importing other packages such as numpy seems to work just fine.