API: give source and destination nodes as separate args to `Edge.__init__`
API: give source and destination nodes as separate args to `Edge.__init__`

no need for `instance` to check whether `src` is a `list` or `tuple`.
If you want to pass an existing tuple `t = (src, dst)`,
then unpack it, for example `Edge(*t, ...)`.

pydot/pydot,erocarrera/pydot