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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def relevant_connections(n, _from, to):
 """Construct a connectivity matrix. Args: n (int):
 The dimensions of the matrix _from (tuple[int]):
 Nodes with outgoing connections to ``to`` to (tuple[int]):
 Nodes with incoming connections from ``_from`` Returns: np.ndarray: An |n x n| connectivity matrix with the |i,jth| entry is ``1`` if |i| is in ``_from`` and |j| is in ``to``, and 0 otherwise. """

    cm = np.zeros((n, n))

    # Don't try and index with empty arrays. Older versions of NumPy
    # (at least up to 1.9.3) break with empty array indices.
    if not _from or not to:
        return cm

    cm[np.ix_(_from, to)] = 1
    return cm