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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 column_of_time(path, start, end=-1):
 """This function extracts the column of times from a ProCoDA data file. :param path: The file path of the ProCoDA data file. If the file is in the working directory, then the file name is sufficient. :type path: string :param start: Index of first row of data to extract from the data file :type start: int :param end: Index of last row of data to extract from the data. Defaults to last row :type end: int :return: Experimental times starting at 0 day with units of days. :rtype: numpy.array :Examples: .. code-block:: python time = column_of_time("Reactor_data.txt", 0) """

    df = pd.read_csv(path, delimiter='\t')
    start_time = pd.to_numeric(df.iloc[start, 0])*u.day
    day_times = pd.to_numeric(df.iloc[start:end, 0])
    time_data = np.subtract((np.array(day_times)*u.day), start_time)
    return time_data