LpVariable dicts issue parsing indices of the form [(a1, b1, c1), (a2, b2, c2), ..., (an, bn, cn)]

[hdelrio]

Details for the issue

When creating a collection of LpVariables using the class method dicts, using an index that is a list of tuples in order to emulate a matrix it only work when the name does not contain a '%'

What did you do?

i1 = list(range(10))
i2 = list('abcdefghij')
i3 = 'jan feb mar apr may jun jul aug sep oct'.split()
indices = [(a, b, c) for a in i1 for b in i2 for c in i3]

P = pl.LpVariable.dicts('P', indices=indices)
P[0, 'a', 'jan']

What did you expect to see?

I was expecting to see: P_(0, 'a', 'jan')

What did you see instead?

P_(0,'a','jan')

Which is a weird looking name

[pchtsp]

I'm not sure if the formatting from github is changing the output. Because I see the same variable name...