Very difficult Real Analysis question on Lebesgue integration

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Suppose gn are nonnegative and integrable on [0, 1], and that gn [tex]\rightarrow[/tex] g almost everywhere.

Further suppose that for all [tex]\epsilon[/tex] > 0, [tex]\exists[/tex] [tex]\delta[/tex] > 0 such that for all A [tex]\subset[/tex] [0, 1], we have

meas(A) < [tex]\delta[/tex] implies that supn [tex]\int[/tex]A |gn| < [tex]\epsilon[/tex].

Prove that g is integrable, and that [tex]\int[/tex][0,1] g = lim [tex]\int[/tex][0,1] gn.

Attempt at the solution:
There are some observations I've compiled. First, for an set A with measure less than [tex]\delta[/tex], we know that the the limiting function g exists on that set. So, it's integral is also bounded by the sup. But from here, I don't know how to argue that the limiting function has a uniform bound on all of [0, 1].
 
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Have you tried any of the well-known theorems in Lebesgue integration regarding interchange of limit and integral?