'a:':
- sum(dimensions=['i'], weights=None, ...)
- 'a:i':
  - data_for_quantity('par', 'a', 'value', ...)
  - 'scenario':
    - <ixmp.core.Scenario object at {id}>
  - 'config':
    - {{'filters': {{}}}}

'b:':
- sum(dimensions=['j'], weights=None, ...)
- 'b:j':
  - data_for_quantity('par', 'b', 'value', ...)
  - 'scenario' (above)
  - 'config' (above)

'cost-margin:':
- data_for_quantity('equ', 'cost', 'mrg', ...)
- 'scenario' (above)
- 'config' (above)

'cost:':
- data_for_quantity('equ', 'cost', 'lvl', ...)
- 'scenario' (above)
- 'config' (above)

'd:':
- sum(dimensions=['i', 'j'], weights=None, ...)
- 'd:i-j':
  - data_for_quantity('par', 'd', 'value', ...)
  - 'scenario' (above)
  - 'config' (above)

'd:i':
- sum(dimensions=['j'], weights=None, ...)
- 'd:i-j' (above)

'd:j':
- sum(dimensions=['i'], weights=None, ...)
- 'd:i-j' (above)

'demand-margin:j':
- data_for_quantity('equ', 'demand', 'mrg', ...)
- 'scenario' (above)
- 'config' (above)

'demand:':
- sum(dimensions=['j'], weights=None, ...)
- 'demand:j':
  - data_for_quantity('equ', 'demand', 'lvl', ...)
  - 'scenario' (above)
  - 'config' (above)

'f:':
- data_for_quantity('par', 'f', 'value', ...)
- 'scenario' (above)
- 'config' (above)

'i':
- ['seattle', 'san-diego']

'j':
- ['new-york', 'chicago', 'topeka']

'supply-margin:i':
- data_for_quantity('equ', 'supply', 'mrg', ...)
- 'scenario' (above)
- 'config' (above)

'supply:':
- sum(dimensions=['i'], weights=None, ...)
- 'supply:i':
  - data_for_quantity('equ', 'supply', 'lvl', ...)
  - 'scenario' (above)
  - 'config' (above)

'x:':
- sum(dimensions=['i', 'j'], weights=None, ...)
- 'x:i-j':
  - data_for_quantity('var', 'x', 'lvl', ...)
  - 'scenario' (above)
  - 'config' (above)

'x:i':
- sum(dimensions=['j'], weights=None, ...)
- 'x:i-j' (above)

'x:j':
- sum(dimensions=['i'], weights=None, ...)
- 'x:i-j' (above)

'z:':
- data_for_quantity('var', 'z', 'lvl', ...)
- 'scenario' (above)
- 'config' (above)

'all':
- list of:
  - 'a:i' (above)
  - 'b:j' (above)
  - 'cost-margin:' (above)
  - 'cost:' (above)
  - 'd:i-j' (above)
  - 'demand-margin:j' (above)
  - 'demand:j' (above)
  - 'f:' (above)
  - 'supply-margin:i' (above)
  - 'supply:i' (above)
  - 'x:i-j' (above)
  - 'z:' (above)
