human
I wrote the below code

    (_, num_columns) = shape(data)
    def matrix_entry(i, j):
        return correlation(get_column(data, i), get_column(data, j))
    return make_matrix(num_columns, num_columns, matrix_entry)

What's a good function header?

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Here's a good function header?
assistant
#Here's a good function header.

def correlation_matrix(data):