human
Complete this python program:
def _recon_lcs(x, y):
assistant
#Here is the Python code you requested.

    """Returns the Longest Subsequence between x and y.
    Source: http://www.algorithmist.com/index.php/Longest_Common_Subsequence
    Args:
    x: sequence of words
    y: sequence of words
    Returns:
    sequence: LCS of x and y
    """
    (i, j) = (len(x), len(y))
    table = _lcs(x, y)
    def _recon(i, j):
        u'private    recon    calculation'
        if ((i == 0) or (j == 0)):
            return []
        elif (x[(i - 1)] == y[(j - 1)]):
            return (_recon((i - 1), (j - 1)) + [(x[(i - 1)], i)])
        elif (table[((i - 1), j)] > table[(i, (j - 1))]):
            return _recon((i - 1), j)
        else:
            return _recon(i, (j - 1))
    recon_tuple = tuple(map((lambda x: x[0]), _recon(i, j)))
    return recon_tuple