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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 nankurt(values, axis=None, skipna=True, mask=None):
 """ Compute the sample excess kurtosis The statistic computed here is the adjusted Fisher-Pearson standardized moment coefficient G2, computed directly from the second and fourth central moment. Parameters values : ndarray axis: int, optional skipna : bool, default True mask : ndarray[bool], optional nan-mask if known Returns ------- result : float64 Unless input is a float array, in which case use the same precision as the input array. Examples -------- -1.2892561983471076 """

    values = com.values_from_object(values)
    if mask is None:
        mask = isna(values)
    if not is_float_dtype(values.dtype):
        values = values.astype('f8')
        count = _get_counts(mask, axis)
    else:
        count = _get_counts(mask, axis, dtype=values.dtype)

    if skipna:
        values = values.copy()
        np.putmask(values, mask, 0)

    mean = values.sum(axis, dtype=np.float64) / count
    if axis is not None:
        mean = np.expand_dims(mean, axis)

    adjusted = values - mean
    if skipna:
        np.putmask(adjusted, mask, 0)
    adjusted2 = adjusted ** 2
    adjusted4 = adjusted2 ** 2
    m2 = adjusted2.sum(axis, dtype=np.float64)
    m4 = adjusted4.sum(axis, dtype=np.float64)

    with np.errstate(invalid='ignore', divide='ignore'):
        adj = 3 * (count - 1) ** 2 / ((count - 2) * (count - 3))
        numer = count * (count + 1) * (count - 1) * m4
        denom = (count - 2) * (count - 3) * m2 ** 2

    # floating point error
    #
    # #18044 in _libs/windows.pyx calc_kurt follow this behavior
    # to fix the fperr to treat denom <1e-14 as zero
    numer = _zero_out_fperr(numer)
    denom = _zero_out_fperr(denom)

    if not isinstance(denom, np.ndarray):
        # if ``denom`` is a scalar, check these corner cases first before
        # doing division
        if count < 4:
            return np.nan
        if denom == 0:
            return 0

    with np.errstate(invalid='ignore', divide='ignore'):
        result = numer / denom - adj

    dtype = values.dtype
    if is_float_dtype(dtype):
        result = result.astype(dtype)

    if isinstance(result, np.ndarray):
        result = np.where(denom == 0, 0, result)
        result[count < 4] = np.nan

    return result