How do I add my dictionary to prettytable - python-3.x

Question

I have two files students and grades that has to be read and converted to a dictionary and finally print to a prettytable:
Grades:
10103 SSW 567 A 98765
10103 SSW 564 A- 98764
10103 CS 501 B 98764
10115 SSW 567 A 98765
10115 SSW 564 B+ 98764
Students:
10103 Baldwin, C SFEN
10115 Wyatt, X SFEN
Below is the code to do that:
from collections import defaultdict
from prettytable import PrettyTable
import os
class University:
def __init__(self,path):
self.students=dict()
self.instructors=dict()
self.grades=defaultdict(list)
def gg(self):
for filename in os.listdir(self.path):
with open(os.path.join(self.path, filename), 'r') as f:
if filename=="students.txt":
for line in f:
a,b,c = line.split("\t")
self.students[a] = {
"name": b, "major": c}
elif filename=="grades.txt":
for line in f:
d,e,f,g = line.split("\t")
self.grades[d].append({
"course": e, "grade": f,"instructor":g})
pt: PrettyTable = PrettyTable(
field_names=[
'CWID',
'Name',
'cc',])
for i,j in self.students.items():
for x,y in self.grades.items():
if i==x:
pt.add_row([i,j["name"],y["course"]])
return pt
a = University("C://Users/Swayam/Documents/Downloads")
c = a.gg()
print(c)
The output is supposed to be:
10103 Baldwin,C SSW567,SSW564,CS501
10115 Wyatt, X SSW 567,SSW564
When I run the above code I get the below error:
TypeError: list indices must be integers or slices, not str
I am not supposed to use the variables in the add_row line and I know that, but what can I replace it with so I get the output.

Answer 1

The issue with your code is that y is a list:
for i,j in self.students.items():
for x,y in self.grades.items():
print(type(y))
>>> <class 'list'>
This is because of you code where you define grades:
self.grades=defaultdict(list)
So, you need some extra code to go through the list of dictionaries:
courses = ",".join(h["course"] for h in y)
And so, the final code becomes:
from collections import defaultdict
from prettytable import PrettyTable
import os
class University:
def __init__(self, path):
self.students = dict()
self.instructors = dict()
self.grades = defaultdict(list)
self.path = path
def gg(self):
for filename in os.listdir(self.path):
with open(os.path.join(self.path, filename), "r") as f:
if filename == "students.txt":
for line in f:
a, b, c = line.split("\t")
self.students[a] = {"name": b, "major": c}
elif filename == "grades.txt":
for line in f:
d, e, f, g = line.split("\t")
self.grades[d].append(
{"course": e, "grade": f, "instructor": g}
)
pt: PrettyTable = PrettyTable(
field_names=[
"CWID",
"Name",
"cc",
]
)
for i, j in self.students.items():
for x, y in self.grades.items():
if i == x:
courses = ",".join(h["course"] for h in y)
pt.add_row([i, j["name"], courses])
return pt
a = University("C://Users/Swayam/Documents/Downloads")
c = a.gg()
print(c)
I get this output when running the above code:
+-------+------------+------------------------+
| CWID | Name | cc |
+-------+------------+------------------------+
| 10103 | Baldwin, C | SSW 567,SSW 564,CS 501 |
| 10115 | Wyatt, X | SSW 567,SSW 564 |
+-------+------------+------------------------+
Note however that I did have to change:
The split you were using to regex split since \t wasn't getting recognised for me
Added self.path = path to your __init__ method
Of course, the path too