results.txt

['Mary', 'Joe', 'Bill', 'Annie', 'Jorge'] = 205   Key votes: []
['Mary', 'Joe', 'Bill', 'Annie'] = 125   Key votes: ['Bill', 'Annie']
['Mary', 'Joe', 'Bill', 'Jorge'] = 135   Key votes: ['Jorge']
['Mary', 'Joe', 'Annie', 'Jorge'] = 175   Key votes: ['Jorge']
['Mary', 'Joe', 'Jorge'] = 105   Key votes: ['Mary', 'Joe', 'Jorge']
['Mary', 'Bill', 'Annie', 'Jorge'] = 185   Key votes: []
['Mary', 'Bill', 'Annie'] = 105   Key votes: ['Mary', 'Bill', 'Annie']
['Mary', 'Bill', 'Jorge'] = 115   Key votes: ['Bill', 'Jorge']
['Mary', 'Annie', 'Jorge'] = 155   Key votes: ['Annie', 'Jorge']
['Joe', 'Bill', 'Annie', 'Jorge'] = 200   Key votes: []
['Joe', 'Bill', 'Annie'] = 120   Key votes: ['Joe', 'Bill', 'Annie']
['Joe', 'Bill', 'Jorge'] = 130   Key votes: ['Bill', 'Jorge']
['Joe', 'Annie', 'Jorge'] = 170   Key votes: ['Annie', 'Jorge']
['Bill', 'Annie', 'Jorge'] = 180   Key votes: ['Jorge']
['Bill', 'Jorge'] = 110   Key votes: ['Bill', 'Jorge']
['Annie', 'Jorge'] = 150   Key votes: ['Annie', 'Jorge']

Owners:   {'Mary': 5, 'Joe': 20, 'Bill': 30, 'Annie': 70, 'Jorge': 80}
Power:    {'Mary': 2, 'Joe': 2, 'Bill': 6, 'Annie': 6, 'Jorge': 10}

voting_power.py

from itertools import combinations,permutations,product

# Inputs: a map between owners and amount of stocks they own and vote modes
stocks = { "Mary":5, "Joe":20, "Bill":30, "Annie":70, "Jorge":80 }
vote_types = ["Y","N"]

# Separate arrays for easier processing later
names = list(stocks.keys())
total = sum(stocks.values())

# Create a dictionary to count voting power for each individual
voting_power = dict([ (name,0) for name in names ])

# Create a table with all the voting possibilities
vote_table = [ vote_types for name in names ]

# Iterate over all the possible outcomes
for votes in product( *vote_table ):

    # Find the index of everyone who voted yes
    votes_yes = [ name for name,vote in zip(names,votes) if vote=='Y' ]

    # Get the vote ownership of those who voted yes and compute the total
    stocks_yes = [ stocks[name] for name in votes_yes ]
    total_votes = sum(stocks_yes)

    # Check if the vote was enough to win
    if total_votes >= total/2:

        # For each person who voted yes, remove them and see if it still passes
        votes_plus = []
        for name in votes_yes:
            partial_sum = total_votes - stocks[name]
            if partial_sum < total/2:

                # If it does not pass, this person is important, has vote power
                voting_power[name] += 1
                votes_plus.append( name )

        # Print the names of the voters, the total of votes and the names of who got a plus
        print( votes_yes , '=', total_votes, "  Key votes:", votes_plus )

# Print the results
print( "\nOwners:  ", stocks )
print( "Power:   ", voting_power )