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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 _ensure_array_list(arrays):
 """Ensures that every element in a list is an instance of a numpy array."""

    # Note: the isinstance test is needed below so that instances of FieldArray
    # are not converted to numpy arrays
    return [numpy.array(arr, ndmin=1) if not isinstance(arr, numpy.ndarray)
            else arr for arr in arrays]