Add other python functions to the syntatic sugar transformer

[gordonwatts]

It would be nice to use more python idioms in func_adl. A complete set in python 3.10.2 can be found here. A lot of them (filter, map, etc.) could be useful. A stretch goal would be enumerate which would allow you to do object pairing when you had a symmetric pairing function. This last perhaps does not belong here as it will require backend modifications.

[alexander-held]

Another useful feature would be support for list comprehensions. When Selecting many columns without the need to change names, there is a risk for typos (and lots of duplicate text) that could be avoided in that manner.

from func_adl_uproot import UprootDataset

dataset_opendata = "https://xrootd-local.unl.edu:1094//store/user/AGC/nanoAOD/TT_TuneCUETP8M1_13TeV-powheg-pythia8/"\
    "cmsopendata2015_ttbar_19980_PU25nsData2015v1_76X_mcRun2_asymptotic_v12_ext3-v1_00000_0000.root"

ds = UprootDataset(dataset_opendata, "Events")
# jet_query = ds.Select(lambda e: {"jet_pt": e["Jet_pt"], "jet_eta": e.Jet_eta})  # this works
jet_query = ds.Select(lambda e: {branch: getattr(e, branch) for branch in ["Jet_pt", "Jet_eta"]})  # does not work
# jet_query = ds.Select("lambda e: {" + ",".join(f"{repr(branch)}: e[{repr(branch)}]" for branch in ["Jet_pt", "Jet_eta"]) + "}")  # works via strings
print(jet_query.value())

The example above result in NameError: Unknown id: branch. @masonproffitt suggested the string-based approach as a workaround, which does work, but suffers from not being too readable (and no syntax highlighting in strings). Instead of getattr, another way to do this would be e[branch], but runs into the same problem.

I am not sure if there is any way to make this work with func_adl.func_adl_callable instead.