Locate the position of the first occurrence of substr column in the given string.
    Returns null if either of the arguments are null.

    .. note:: The position is not zero based, but 1 based index. Returns 0 if substr
        could not be found in str.

    >>> df = spark.createDataFrame([('abcd',)], ['s',])
    >>> df.select(instr(df.s, 'b').alias('s')).collect()
    [Row(s=2)]

def instr(str, substr):
    """
    Locate the position of the first occurrence of substr column in the given string.
    Returns null if either of the arguments are null.

    .. note:: The position is not zero based, but 1 based index. Returns 0 if substr
        could not be found in str.

    >>> df = spark.createDataFrame([('abcd',)], ['s',])
    >>> df.select(instr(df.s, 'b').alias('s')).collect()
    [Row(s=2)]
    """
    sc = SparkContext._active_spark_context
    return Column(sc._jvm.functions.instr(_to_java_column(str), substr))