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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 file_loc():
 """Return file and line number"""

    import sys
    import inspect
    try:
        raise Exception
    except:
        file_ = '.../' + '/'.join((inspect.currentframe().f_code.co_filename.split('/'))[-3:])
        line_ = sys.exc_info()[2].tb_frame.f_back.f_lineno
        return "{}:{}".format(file_, line_)