For the given data from the amazon reviews, perform the below activities:

1. Clean the data

2. Plot a bigram bar graph on the top words 25 words

3. Find customer concern areas - the top 25 bigrams which includes the below negative words indicating the customer concern areas

'poor', 'waste', 'bad', 'defective', 'disgusting', 'untrusty', 'worst', 'horrible', 'unexpectedly', 'slow'

4. Plot a bar graph for the top 25 customer concern areas

Write code in Python

sample data set:

asin	helpful	overall	reviewText	reviewTime	reviewerID	reviewerName	summary	unixReviewTime
528881469	[0, 0]	5	We got this GPS for my husband who is an (OTR) over the road trucker. Very Impressed with the shipping time, it arrived a few days earlier than expected... within a week of use however it started freezing up... could of just been a glitch in that unit. Worked great when it worked! Will work great for the normal person as well but does have the "trucker" option. (the big truck routes - tells you when a scale is coming up ect...) Love the bigger screen, the ease of use, the ease of putting addresses into memory. Nothing really bad to say about the unit with the exception of it freezing which is probably one in a million and that's just my luck. I contacted the seller and within minutes of my email I received a email back with instructions for an exchange! VERY impressed all the way around!	06 2, 2013	AO94DHGC771SJ	amazdnu	Gotta have GPS!	1370131200
528881469	[12, 15]	1	I'm a professional OTR truck driver, and I bought a TND 700 at a truck stop hoping to make my life easier. Rand McNally, are you listening?First thing I did after charging it was connect it to my laptop and install the software and then attempt to update it. The software detected a problem with my update and wanted my home address so I could be sent a patch on an SD card. Hello? I don't think I'm all that unusual; my home address is a PO box that a friend checks weekly and that I might get to check every six months or so. I live in my truck and at truck stops. If you need to make a patch available on an SD card then you should send the SD cards to the truck stops where the devices are sold. I ran the update program multiple times until the program said that the TND 700 was completely updated.I programmed in the height (13'6"), the length (53') and the weight (80,000#) of my rig and told it that I preferred highways. I was parked at a truck stop in the Cincinnati OH area. My next pickup was about 15 miles down the same freeway but on the other side of it a couple of blocks. My cell phone GPS (Sprint) said to get on the freeway to get to my pickup. The TND 700 routed me thru 23 miles of residential streets before finally getting me to my pickup. Very exciting, especially since every time I refused to turn down a street posted "No Trucks" the TND 700 took almost 5 minutes to figure a re-route, and it happened multiple times on that short trip.I decided to give it another chance. After my pickup on the north side of Cincinnati just off of I-75 I needed to head to Phoenix AZ via I-71. Easy route is to just hop on I-75 and drive west and south to the intersection of I-71. Indeed, that is what my cell phone advised. The TND 700, however, wanted to route me over surface streets across the city and pick up I-75 on the other side of the city. I turned it off and the next time I passed a truck stop of the same chain I purchased it at I returned it and got my money back.I then spent $30 on a cheap printer. Now I take a minute to set up my route on Google and print it out. Hasn't gotten me lost yet over several cross country trips.	11 25, 2010	AMO214LNFCEI4	Amazon Customer	Very Disappointed	1290643200
528881469	[43, 45]	3	Well, what can I say. I've had this unit in my truck for about four days now. Prior to that I had a Garmin 755T non-truck GPS. One of my favorite features in that unit was the ability to plan a route by determining mileage using the stop or via feature. What I would do is using a map I would route myself several different ways forcing the unit by putting in stops or vias at different locations along the route, otherwise, like most GPS 's, it determines what it thinks is the best route. I could add up to 10 Via's or stop points for each route and then based on mileage and other factors determine which is the best route to take. Multiple stops and the ability to route was the most important reason for having the Garmin. However it was not truck specific. And considering I am now hauling strictly hazmat I wanted something that would take that into consideration. After perusing various forums, review sites, and word-of-mouth my choices boiled down to the Garmin 465T or the RAND McNally Intelliroute TND 700. Even though it was quite a bit more than the Garmin I chose the TND 700 for several reasons. The main one being the extra screen size, and its ability to coordinate with the RAND McNally truck atlas and also its ease of updating.Now on to my first impression of the TND 700. It seems to be an aesthetically pleasing and durably built unit. The first thing I noticed was it's very slow to boot compared to my old Garmin. Whether this is unique to the TND 700 or is common amongst all truck specific gps units I cannot tell, but it's really not that big of a deal. The second thing I noticed was the overwhelming wealth of information put forth. That might explain why the manual (available via the TND dock) is well over 100 pages long..... There is somewhat of a learning curve with this unit. The next thing I noticed was the complexity of entering routes. As previously mentioned I like to force it into my preferred routing by the use of stops or vias. That was a big no go with this unit. While you can enter multiple stops or vias it is nowhere near as user-friendly as my old Garmin. Furthermore there is no way you can determine total mileage on the route that you have chosen	09 9, 2010	A3N7T0DY83Y4IG	C. A. Freeman	1st impression	1283990400
528881469	[9, 10]	2	Not going to write a long review, even thought this unit deserves one. I've driven well over 1-mil miles and done most of my own routing so I pretty know whats the fastest and shortest. Have been using a basic garmin for the past three years and with ANY Gps unit they'll ALL get you in trouble if you let them. I was really excited about this unit, due to the size and the features. Allot of great grafics and on screen info thats usefull. But the most basic item that it was lacking was the gps tracking. I gave this unit allot of leadway on its mistakes due to the fact that it had allot of cool stuff that it did, but its ability to track you and route you was not even close to what the basic garmin could due. Its like the prossesor that they installed in the TND 700 was 10 years old. Example if I needed to make a simple route change I.E. in town down to the next street due to the fact that I couldn't make the turn or the street was blocked off, it would take the TND 700 upwards of 45 seconds to a minute and a half to reroute me. Here I'm sitting at a stop light waiting for directions and waiting that long with cars on my backside didn't make me happy. This is a problem that happened evertime you had to reroute, weather it was a simple street change or a major highway change. Also from the time you turned the unit on it would take twice as long to boot itself up. At least a dozen times with in a week it put me on the wrong roads and when I made a wrong turn it got it self lost....I.E. take left on xyz street, and it was some ones drive way. Or turn left in 800 yards and the turn was less than 10 feet away. You might think in a conjested city situation I might get a little mixed up, but this is out in the country. Twice it put me under 12'6" bridges when I'm 13'6". Of course I made sure all my truck setting where they were supposed to be. I also updated the OS version,via Rand McNally. All in all I expected alot out of this unit and got a unit that should of been field tested with some people that drive allot. It just had to many route mistakes. Going back to the basic garmin. This isn't just my complaints, I have three friends that bought the same unit and have the same complaints. All of us returned the units.	11 24, 2010	A1H8PY3QHMQQA0	Dave M. Shaw "mack dave"	Great grafics, POOR GPS	1290556800

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