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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 char_conv(out):
 """ Convert integer vectors to character vectors for batch. """

    out_conv = list()
    for i in range(out.shape[0]):
        tmp_str = ''
        for j in range(out.shape[1]):
            if int(out[i][j]) >= 0:
                tmp_char = int2char(int(out[i][j]))
                if int(out[i][j]) == 27:
                    tmp_char = ''
                tmp_str = tmp_str + tmp_char
        out_conv.append(tmp_str)
    return out_conv