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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 _ints_arr_to_bits(ints_arr, out):
 """ Convert an array of integers representing the set bits into the corresponding integer. Compiled as a ufunc by Numba's `@guvectorize`: if the input is a 2-dim array with shape[0]=K, the function returns a 1-dim array of K converted integers. Parameters ints_arr : ndarray(int32, ndim=1) Returns ------- np.uint64 Integer with set bits represented by the input integers. Examples -------- 7 array([ 7, 11], dtype=uint64) """

    m = ints_arr.shape[0]
    out[0] = 0
    for i in range(m):
        out[0] |= np.uint64(1) << np.uint64(ints_arr[i])