Exercise

# Finding open triangles

Let us now move on to finding open triangles! Recall that they form the basis of friend recommendation systems; if "A" knows "B" and "A" knows "C", then it's probable that "B" also knows "C".

Instructions

**100 XP**

- Write a function
`node_in_open_triangle()`

that has two parameters -`G`

and`n`

- and identifies whether a node is present in an open triangle with its neighbors.- In the
`for`

loop, iterate over all possible triangle relationship combinations. - If the nodes
`n1`

and`n2`

do*not*have an edge between them, set`in_open_triangle`

to`True`

, break out from the`if`

statement and return`in_open_triangle`

.

- In the
- Use this function to count the number of open triangles that exist in
`T`

.- In the
`for`

loop, iterate over all the nodes in`T`

. - If the current node
`n`

is in an open triangle, increment`num_open_triangles`

.

- In the