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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 get_modification_datetime(filepath):
 """ Get the datetime that a file was last modified. Parameters filepath : str Returns ------- modification_datetime : datetime.datetime """

    import tzlocal
    timezone = tzlocal.get_localzone()
    mtime = datetime.fromtimestamp(os.path.getmtime(filepath))
    return mtime.replace(tzinfo=timezone)