Find Bridges in a Graph

An edge in an undirected connected graph is a bridge if removing it disconnects the graph. 
Given a graph with node from 1 to n, and a list of integer pairs represent edges, return all the bridges. 

n = 4
edges = [[1, 2], [1, 3], [1, 4]]

[[1, 2], [1, 3], [1, 4]]

If any of the edges removed, the graph will be disconnected. 

n = 4
edges = [[1, 2], [1, 3], [2, 3]]


No bridges. 

Solve the problem:
def findBridges(n, edges):

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