Can someone take a look or try running my solution to the challenge and suggest why it’s not passing the tests?

I’ve ran all the requirements through with CodeRunner and get identical output to the specs but it is still failing in the web app.

```
def arithmetic_arranger(*arguments):
#!check for length of problems
problems = arguments[0][0]
if len(problems) > 5:
print('Error: Too many problems.')
return 'Error: Too many problems.'
# create a dictionary to store the lines for all the equations
lines_dict = dict()
for item in ['line_1','line_2','line_3','line_4']:
lines_dict[item] = []
for item in problems:
# split item into equation_split
equation_split = item.split()
# extract operands and operator
if len(equation_split[0]) <= 4 and len(equation_split[2]) <= 4:
if isinstance(int(equation_split[0]),int) and isinstance(int(equation_split[2]),int):
operand1 = equation_split[0]
operand2 = equation_split[2]
#print(operand1,operand2)
else:
print('Error: Numbers must only contain digits.')
return 'Error: Numbers must only contain digits.'
else:
print('Error: Numbers cannot be more than four digits.')
return 'Error: Numbers cannot be more than four digits'
if equation_split[1] == '+' or equation_split[1] == '-':
operator = equation_split[1]
else:
print('Error: Operator must be '+' or '-'.')
return 'Error: Operator must be '+' or '-'.'
# calculate length of biggest operand (longest number)
max_operand_len = max(len(operand1),len(operand2))
#print("max operand len",max_operand_len)
# calculate the display length for each equation
display_len = max_operand_len + 2
# 1st line
first_line = ''
## calculate spaces before 1st operand (32)
spaces = display_len - len(operand1)
## add spaces to first_line
first_line = spaces * ' '
## add operand to first line
first_line += operand1
lines_dict['line_1'].append(first_line)
#print(lines_dict["line_1"])
# 2nd line
second_line = '{}'.format(operator)
## calculate spaces to line_2
spaces = (display_len - 1) - len(operand2)
## add spaces to line_2
second_line += spaces * ' '
## add operand2 to line_2
second_line += operand2
lines_dict['line_2'].append(second_line)
#print(lines_dict["line_2"].
# 3rd line
third_line = '-' * display_len
lines_dict['line_3'].append(third_line)
#print(lines_dict["line_3"])
# 4th line
fourth_line = ''
## calculate answer
answer = None
if operator == '+':
answer = str(int(operand1) + int(operand2))
else:
answer = str(int(operand1) - int(operand2))
## calculate spaces
spaces = display_len - len(str(answer))
## add spaces to fourth_line
fourth_line = spaces * ' '
## add answer to fourth_line
fourth_line += answer
lines_dict['line_4'].append(fourth_line)
# join (seperated by 4 spaces) and print the lines in lines_dict
if not arguments[0].__contains__(True):
lines_dict.__delitem__('line_4')
arranged_problems = ""
for item in lines_dict:
arranged_problems += ' '.join(lines_dict[item]) + '\n'
print(arranged_problems)
#return ("{}\n{}\n{}\n{}".format(first_line,second_line,third_line,fourth_line))
return arranged_problems
```