Please explain why three?

Question

numbers=['one','two','three','four']
num_dict={x[0]: x for x in numbers}
print(num_dict['t'])

Answer 1

In the second line {x[0]: x for x in numbers}. Since string can be act like a list of characters. It would return a dictionary like this:
{
'one'[0]: 'one',
'two'[0]: 'two',
'three'[0]: 'three',
'four'[0]: 'four'
}

When there is duplicate key in a dictionary, use the last value.
So num_dict['t'] would return 'three'.

Answer 2

The for loop runs the values of the numbers list and it adds to a dictionary the first letter of every value as a key and the value itself as a value then the dictionary looks this way:
{'o':'one', 't':'three', 'f', 'four'}