infer_ops.jl fails
```
ERROR: LoadError: MethodError: no method matching fadd(::Int64, ::Float64)
Closest candidates are:
  fadd(!Matched::Int8, ::Float64) at /Users/john.vandenberg/python/py2many/tests/cases/infer_ops.jl:63
Stacktrace:
 [1] show()
   @ Main ~/python/py2many/tests/cases/infer_ops.jl:68
 [2] main()
   @ Main ~/python/py2many/tests/cases/infer_ops.jl:75
 [3] top-level scope
   @ ~/python/py2many/tests/cases/infer_ops.jl:78
```