def is_connection_dropped(conn):
    if not poll: # Platform-specific
        return select([conn.sock], [], [], 0.0)[0]

    # This version is better on platforms that support it.
    p = poll()
    p.register(conn.sock, POLLIN)
    for (fno, ev) in p.poll(0.0):
        if fno == conn.sock.fileno():
            # Either data is buffered (bad), or the connection is dropped.
            return True
Compute F matrix from E matrix.
dataset/ETHPy150Open lmorchard/badg.us/vendor-local/lib/python/requests/packages/urllib3/connectionpool.py/is_connection_dropped--crossover with--dataset/ETHPy150Open biocore/scikit-bio/skbio/stats/ordination/_utils.py/f_matrix