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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 read_discrete_trajectory(filename):
 """Read discrete trajectory from ascii file. The ascii file containing a single column with integer entries is read into an array of integers. Parameters filename : str The filename of the discrete state trajectory file. The filename can either contain the full or the relative path to the file. Returns ------- dtraj : (M, ) ndarray Discrete state trajectory. """

    with open(filename, "r") as f:
        lines=f.read()
        dtraj=np.fromstring(lines, dtype=int, sep="\n")
        return dtraj