cs50 readability pset6 python - Index calculation Issue - python

An Index calculation Issue in my pset6 readability
This is my code and I think it is correct but, the grade for every paragraph is wrong because the index calculation is wrong. Although, the letters, words, and sentence counting is correct. So, where is the problem? someone help me, please?
from cs50 import get_string
import math
# Loop to count the letters
letters = 0
words = 0
sentences = 0
# Prompt user for some text.
text = get_string("Text: ")
# Loop to count the letters(s) of a paragraph
def count_letters():
global letters
for i in range(len(text)):
if text[i].lower() or text[i].upper():
letters += 1
# pass
print(letters)
return letters
count_letters()
# Loop to count the words of the paragraph.
def count_words():
global words
for i in range(len(text)):
if text[i].isspace():
words += 1
# TODO
if text[i].isspace() and text[i + 1].isspace():
words -= 1
print(words + 1)
return words + 1
count_words()
# Loop to count sentences of the paragraph.
def count_sentences():
global sentences
for i in range(len(text)):
if text[i] == "." or text[i] == "!" or text[i] == "?":
sentences += 1
print(sentences)
return sentences
count_sentences()
# Calc the index of the grades
def indexOfGrade():
global letters
global words
global sentences
l = letters / words * 100
s = sentences / words * 100
index = round(0.0588 * l - 0.296 * s - 15.8)
print(letters / words)
print(l)
print(s)
print(index)
# grades
if index >= 16:
print("Grade 16+")
elif index < 1:
print("Before Grade 1")
else:
print(f"Grade {index}")
indexOfGrade()

Yahooo, after a lot of time I figured out your mistake.
def count_words():
global words
for i in range(len(text)):
if text[i].isspace():
words += 1
# TODO
if text[i].isspace() and text[i + 1].isspace():
words -= 1
print(words + 1)
return words + 1 #This part is wrong
The last line, which is return will just return the value but will not change the value of the variable words, therefore, you need to correct it as follows
def count_words():
global words
for i in range(len(text)):
if text[i].isspace():
words += 1
# TODO
if text[i].isspace() and text[i + 1].isspace():
words -= 1
print(words + 1)
words += 1
return words
Also the letters, words and sentences variables may optionally be float and not int and while calculating the index, python will omit the remaining decimal part, therefore the round may not work.
Also, I have performed check50 on my device and all the results were green with (correct)
Also, if text[i].isspace() and text[i + 1].isspace(): was wrong you need to completely delete that part.
Therefore here is the final answer with the required changes.
from cs50 import get_string
import math
# Loop to count the letters
letters = float(0)
words = float(0)
sentences = float(0)
# Prompt user for some text.
text = get_string("Text: ")
# Loop to count the letters(s) of a paragraph
def count_letters():
global letters
for i in range(len(text)):
if (text[i] >= 'a' and text[i] <= 'z') or (text[i] >= 'A' and text[i] <= 'Z'):
letters += 1
# pass
# # print(letters)
return letters
count_letters()
# Loop to count the words of the paragraph.
def count_words():
global words
for i in range(len(text)):
if text[i].isspace():
words += 1
# # TODO
# if text[i].isspace() and text[i + 1].isspace():
# pass
# # print(words + 1)
words += 1
return words + 1
count_words()
# Loop to count sentences of the paragraph.
def count_sentences():
global sentences
for i in range(len(text)):
if text[i] == "." or text[i] == "!" or text[i] == "?":
sentences += 1
# # print(sentences)
return sentences
count_sentences()
# Calc the index of the grades
def indexOfGrade():
global letters
global words
global sentences
# print(letters)
# print(words)
# print(sentences)
l = 100 * letters / words
# print(l)
s = sentences / words * 100
# print(s)
index = round(0.0588 * l - 0.296 * s - 15.8)
# # print(letters / words)
# print(0.0588 * l - 0.296 * s - 15.8)
# print(l)
# print(s)
# print(index)
# grades
if index >= 16:
print("Grade 16+")
elif index < 1:
print("Before Grade 1")
else:
print(f"Grade {index}")
indexOfGrade()
Note: you may optionally remove all the comment statements.
Link to my check50 result

Related

cs50 pset6 readability getting wrong grade and negative index

Can anyone spot the issue? I get a negative for my index everytime so it always prints "Before Grade 1". I tried doing some regex but I still don't know how to implement it really
import re
from cs50 import get_string
words = 1
letters = 0
sentences = 0
st = get_string("Text: ")
t = len(st)
regex = r'\w+'
output = re.findall(regex,st)
for i in range(t):
if st.isalpha():
letters += 1
if st.isspace():
words += 1
if st[i] == '.' or st[i] == '!' or st[i] == '?':
sentences += 1
L = (letters / words * 100)
S = (sentences / words * 100)
index = 0.0588 * L - 0.296 * S - 15.8
roundedIndex = round(index)
if roundedIndex < 1:
print("Before Grade 1")
if roundedIndex >= 16:
print("Grade 16+")
else:
print(roundedIndex)
Inside your loop, you're checking if the whole string is alphabetical or a space, not whether the letter corresponding to the index i is. You probably want st[i].isalpha() and st[i].isspace().
Or, you could loop over the characters directly, rather than over indexes:
for char in st:
if char.isalpha():
...
if char.isspace():
...

How can I find this word is Substitutions: or Insertions python

For example, my word is "brain", we need to create function that check is it subsitutions and is it insertions.
For example, Substitutions can be: train grain blain bryin ... Insertions: barain bryain ...
#I am not sure I did the right way or missing something. And any other way that faster?
#string0 is pattern
def subsitutions(string0, string1):
sublist = []
for i in range(len(string0)):
sublist.append(string0[:i] + string0[i + 1:])
for i in range(len(string1)):
if string1[:i] + string1[i + 1:] in sublist:
print("This word is subsitutions")
break
def insertions(string0, string1):
if len(string0)+1 == len(string1):
for i in range(len(string1)):
if string1[:i] + string1[i + 1:] == string0:
print("This word is insertions")
break
set.difference would easily do this for you:
>>> set('brian') - set('bryan')
{'i'}
>>> set('brian') - set('byrian')
set()
Here's a dirty example of this check:
def check_sub_or_ins(pattern, string):
if set(pattern) - set(string):
print("This word is subsitutions")
else:
print("This word is insertions")
You will need to check the length of each string though as just using set won't work for all strings
See if this helps
word = "brain"
word_length = len(word)
words_to_check = ["train", "grain", "blain", "bryin", "barain", "bryain"]
for word_to_check in words_to_check:
boolean_list = [character in word for character in word_to_check]
character_occurences = sum(boolean_list)
if character_occurences == word_length - 1:
print("{0} is substitution".format(word_to_check))
elif character_occurences >= word_length - 1 and len(boolean_list) > word_length:
print("{0} is insertion".format(word_to_check))

I'm trying to perform some manual encoding of strings using python

Probelm Description:
sms_encoding() which accepts a sentence and converts it into an abbreviated sentence to be sent as SMS and returns the abbreviated sentence.
Rules are as follows:
a. Spaces are to be retained as is
b. Each word should be encoded separately
If a word has only vowels then retain the word as is
If a word has a consonant (at least 1) then retain only those consonants
My Code:
#PF-Assgn-50
def sms_encoding(data):
#start writing your code here
vowels=set("aeiouAEIOU")
v_list=[]
c_list=[]
final_list=[]
new_string=''
word=data.split()
word2=[]
for i in range(0,len(word)):
ch=word[i]
#print(ch)
if ch in vowels:
v_list.append(ch)
for letter in word[i]:
if letter not in vowels:
c_list.append(letter)
c_list.append(" ")
new_string=''.join(v_list)+''.join(c_list)
final_list.append(new_string)
#print(v_list)
return ' '.join(final_list)
data="Have a Nice Day"
print(sms_encoding(data))
My Output:
aHv **<2spaces>** Nc **<1space>** Dy
Expected Output:
Hv a Nc Dy (contains only 1 space)
You could iterate over words in the sentence taking only consonants only if the word contains atleast one consonant:
data = "Have a Nice Day"
splitted = data.split()
for i, x in enumerate(splitted):
if not all(y in 'aeiou' for y in x.lower()):
splitted[i] = ''.join([y for y in x if y.lower() not in 'aeiou'])
print(' '.join(splitted))
# Hv a Nc Dy
This will work for all cases... retains all except vowels when even 1 character in a string is not vowel.
def sms_encoding(data):
vowels = set("aeiouAEIOU")
words = data.split()
encoded_words = []
for i in range(0,len(words)):
vow_count = 0
cons_word = []
for x in words[i]:
if x in vowels:
vow_count =vow_count+1
elif x not in vowels:
cons_word.append(x)
if vow_count == len(words[i]):
encoded_words.append(words[i])
elif vow_count != len(words[i]):
encoded_words.append("".join(cons_word))
encoded_msg = " ".join(encoded_words)
return encoded_msg
data=input("Kindly enter your message for sms encoding : ")
print(sms_encoding(data))
Try and let me know!
def sms_encoding(data):
vowel = "aeiouAEIOU"
list1 = data.split()
list2 = []
for i in list1:
length=len(i)
if length == 1:
list2.append(i)
list2.append(" ")#to add spaces between the words
else:
count=0
for a in i:
if a in vowel:
count+=1
if count==length: #to check if all the letters are vowels
list2.append(i)
list2.append(" ")
for a in i:
if a not in vowel:
list2.append(a)
list2.append(" ")
list2.pop() #to remove the extra space at the end of the whole sentence
q="".join(list2)
return q
data = "I love Python aeio"
print(sms_encoding(data))
try this code it will work the question is from infytq
def sms_encoding(data):
data=data.lower()
a=data.split()
v1=""
for i in range(0,len(a)):
z=a[i]
v=""
c1=0
for j in z:
if j not in ('a','e','i','o','u'):
v=v+j
elif j in ('a','e','i','o','u'):
c1=c1+1
if(c1!=len(z)):
v1=v1+v+" "
elif(c1==len(z)):
v1=v1+z+" "
word=v1[0:len(v1)-1]
return word
data="I love Python"
print(sms_encoding(data))
def sms_encoding(new_s):
encrypt_string = []
consonant_list = []
vowel_set = set("aeiouAEIOU")
for word in range(0, len(new_s)):
v_letter = new_s[word]
if v_letter in vowel_set:
encrypt_string.append(v_letter)
for letter in v_letter:
if letter not in vowel_set:
consonant = " ".join(letter)
encrypt_string.append(consonant)
encrypt_string.append(" ")
encrypt_string = "".join(encrypt_string)
print(encrypt_string)
s = input("Enter a string ")
new_s = s.split()
sms_encoding(new_s)

Find the longest substring in alphabetical order

I have this code that I found on another topic, but it sorts the substring by contiguous characters and not by alphabetical order. How do I correct it for alphabetical order? It prints out lk, and I want to print ccl. Thanks
ps: I'm a beginner in python
s = 'cyqfjhcclkbxpbojgkar'
from itertools import count
def long_alphabet(input_string):
maxsubstr = input_string[0:0] # empty slice (to accept subclasses of str)
for start in range(len(input_string)): # O(n)
for end in count(start + len(maxsubstr) + 1): # O(m)
substr = input_string[start:end] # O(m)
if len(set(substr)) != (end - start): # found duplicates or EOS
break
if (ord(max(sorted(substr))) - ord(min(sorted(substr))) + 1) == len(substr):
maxsubstr = substr
return maxsubstr
bla = (long_alphabet(s))
print "Longest substring in alphabetical order is: %s" %bla
s = 'cyqfjhcclkbxpbojgkar'
r = ''
c = ''
for char in s:
if (c == ''):
c = char
elif (c[-1] <= char):
c += char
elif (c[-1] > char):
if (len(r) < len(c)):
r = c
c = char
else:
c = char
if (len(c) > len(r)):
r = c
print(r)
Try changing this:
if len(set(substr)) != (end - start): # found duplicates or EOS
break
if (ord(max(sorted(substr))) - ord(min(sorted(substr))) + 1) == len(substr):
to this:
if len(substr) != (end - start): # found duplicates or EOS
break
if sorted(substr) == list(substr):
That will display ccl for your example input string. The code is simpler because you're trying to solve a simpler problem :-)
You can improve your algorithm by noticing that the string can be broken into runs of ordered substrings of maximal length. Any ordered substring must be contained in one of these runs
This allows you to just iterate once through the string O(n)
def longest_substring(string):
curr, subs = '', ''
for char in string:
if not curr or char >= curr[-1]:
curr += char
else:
curr, subs = '', max(curr, subs, key=len)
return max(curr, subs, key=len)
s = 'cyqfjhcclkbxpbojgkar'
longest = ""
max =""
for i in range(len(s) -1):
if(s[i] <= s[i+1] ):
longest = longest + s[i]
if(i==len(s) -2):
longest = longest + s[i+1]
else:
longest = longest + s[i]
if(len(longest) > len(max)):
max = longest
longest = ""
if(len(s) == 1):
longest = s
if(len(longest) > len(max)):
print("Longest substring in alphabetical order is: " + longest)
else:
print("Longest substring in alphabetical order is: " + max)
In a recursive way, you can import count from itertools
Or define a same method:
def loops( I=0, S=1 ):
n = I
while True:
yield n
n += S
With this method, you can obtain the value of an endpoint, when you create any substring in your anallitic process.
Now looks the anallize method (based on spacegame issue and Mr. Tim Petters suggestion)
def anallize(inStr):
# empty slice (maxStr) to implement
# str native methods
# in the anallize search execution
maxStr = inStr[0:0]
# loop to read the input string (inStr)
for i in range(len(inStr)):
# loop to sort and compare each new substring
# the loop uses the loops method of past
# I = sum of:
# (i) current read index
# (len(maxStr)) current answer length
# and 1
for o in loops(i + len(maxStr) + 1):
# create a new substring (newStr)
# the substring is taked:
# from: index of read loop (i)
# to: index of sort and compare loop (o)
newStr = inStr[i:o]
if len(newStr) != (o - i):# detect and found duplicates
break
if sorted(newStr) == list(newStr):# compares if sorted string is equal to listed string
# if success, the substring of sort and compare is assigned as answer
maxStr = newStr
# return the string recovered as longest substring
return maxStr
Finally, for test or execution pourposes:
# for execution pourposes of the exercise:
s = "azcbobobegghakl"
print "Longest substring in alphabetical order is: " + anallize( s )
The great piece of this job started by: spacegame and attended by Mr. Tim Petters, is in the use of the native str methods and the reusability of the code.
The answer is:
Longest substring in alphabetical order is: ccl
In Python character comparison is easy compared to java script where the ASCII values have to be compared. According to python
a>b gives a Boolean False and b>a gives a Boolean True
Using this the longest sub string in alphabetical order can be found by using the following algorithm :
def comp(a,b):
if a<=b:
return True
else:
return False
s = raw_input("Enter the required sting: ")
final = []
nIndex = 0
temp = []
for i in range(nIndex, len(s)-1):
res = comp(s[i], s[i+1])
if res == True:
if temp == []:
#print i
temp.append(s[i])
temp.append(s[i+1])
else:
temp.append(s[i+1])
final.append(temp)
else:
if temp == []:
#print i
temp.append(s[i])
final.append(temp)
temp = []
lengths = []
for el in final:
lengths.append(len(el))
print lengths
print final
lngStr = ''.join(final[lengths.index(max(lengths))])
print "Longest substring in alphabetical order is: " + lngStr
Use list and max function to reduce the code drastically.
actual_string = 'azcbobobegghakl'
strlist = []
i = 0
while i < len(actual_string)-1:
substr = ''
while actial_string[i + 1] > actual_string[i] :
substr += actual_string[i]
i += 1
if i > len(actual_string)-2:
break
substr += actual-string[i]
i += 1
strlist.append(subst)
print(max(strlist, key=len))
Wow, some really impressing code snippets here...
I want to add my solution, as I think it's quite clean:
s = 'cyqfjhcclkbxpbojgkar'
res = ''
tmp = ''
for i in range(len(s)):
tmp += s[i]
if len(tmp) > len(res):
res = tmp
if i > len(s)-2:
break
if s[i] > s[i+1]:
tmp = ''
print("Longest substring in alphabetical order is: {}".format(res))
Without using a library, but using a function ord() which returns ascii value for a character.
Assumption: input will be in lowercase, and no special characters are used
s = 'azcbobobegghakl'
longest = ''
for i in range(len(s)):
temp_longest=s[i]
for j in range(i+1,len(s)):
if ord(s[i])<=ord(s[j]):
temp_longest+=s[j]
i+=1
else:
break
if len(temp_longest)>len(longest):
longest = temp_longest
print(longest)
Slightly different implementation, building up a list of all substrings in alphabetical order and returning the longest one:
def longest_substring(s):
in_orders = ['' for i in range(len(s))]
index = 0
for i in range(len(s)):
if (i == len(s) - 1 and s[i] >= s[i - 1]) or s[i] <= s[i + 1]:
in_orders[index] += s[i]
else:
in_orders[index] += s[i]
index += 1
return max(in_orders, key=len)
s = "azcbobobegghakl"
ls = ""
for i in range(0, len(s)-1):
b = ""
ss = ""
j = 2
while j < len(s):
ss = s[i:i+j]
b = sorted(ss)
str1 = ''.join(b)
j += 1
if str1 == ss:
ks = ss
else:
break
if len(ks) > len(ls):
ls = ks
print("The Longest substring in alphabetical order is "+ls)
This worked for me
s = 'cyqfjhcclkbxpbojgkar'
lstring = s[0]
slen = 1
for i in range(len(s)):
for j in range(i,len(s)-1):
if s[j+1] >= s[j]:
if (j+1)-i+1 > slen:
lstring = s[i:(j+1)+1]
slen = (j+1)-i+1
else:
break
print("Longest substring in alphabetical order is: " + lstring)
Output: Longest substring in alphabetical order is: ccl
input_str = "cyqfjhcclkbxpbojgkar"
length = len(input_str) # length of the input string
iter = 0
result_str = '' # contains latest processed sub string
longest = '' # contains longest sub string alphabetic order
while length > 1: # loop till all char processed from string
count = 1
key = input_str[iter] #set last checked char as key
result_str += key # start of the new sub string
for i in range(iter+1, len(input_str)): # discard processed char to set new range
length -= 1
if(key <= input_str[i]): # check the char is in alphabetic order
key = input_str[i]
result_str += key # concatenate the char to result_str
count += 1
else:
if(len(longest) < len(result_str)): # check result and longest str length
longest = result_str # if yes set longest to result
result_str = '' # re initiate result_str for new sub string
iter += count # update iter value to point the index of last processed char
break
if length is 1: # check for the last iteration of while loop
if(len(longest) < len(result_str)):
longest = result_str
print(longest);
finding the longest substring in alphabetical order in Python
in python shell 'a' < 'b' or 'a' <= 'a' is True
result = ''
temp = ''
for char in s:
if (not temp or temp[-1] <= char):
temp += char
elif (temp[-1] > char):
if (len(result) < len(temp)):
result = temp
temp = char
if (len(temp) > len(result)):
result = temp
print('Longest substring in alphabetical order is:', result)
s=input()
temp=s[0]
output=s[0]
for i in range(len(s)-1):
if s[i]<=s[i+1]:
temp=temp+s[i+1]
if len(temp)>len(output):
output=temp
else:
temp=s[i+1]
print('Longest substring in alphabetic order is:' + output)
I had similar question on one of the tests on EDX online something. Spent 20 minutes brainstorming and couldn't find solution. But the answer got to me. And it is very simple. The thing that stopped me on other solutions - the cursor should not stop or have unique value so to say if we have the edx string s = 'azcbobobegghakl' it should output - 'beggh' not 'begh'(unique set) or 'kl'(as per the longest identical to alphabet string). Here is my answer and it works
n=0
for i in range(1,len(s)):
if s[n:i]==''.join(sorted(s[n:i])):
longest_try=s[n:i]
else:
n+=1
In some cases, input is in mixed characters like "Hello" or "HelloWorld"
**Condition 1:**order determination is case insensitive, i.e. the string "Ab" is considered to be in alphabetical order.
**Condition 2:**You can assume that the input will not have a string where the number of possible consecutive sub-strings in alphabetical order is 0. i.e. the input will not have a string like " zxec ".
string ="HelloWorld"
s=string.lower()
r = ''
c = ''
last=''
for char in s:
if (c == ''):
c = char
elif (c[-1] <= char):
c += char
elif (c[-1] > char):
if (len(r) < len(c)):
r = c
c = char
else:
c = char
if (len(c) > len(r)):
r = c
for i in r:
if i in string:
last=last+i
else:
last=last+i.upper()
if len(r)==1:
print(0)
else:
print(last)
Out:elloW
```python
s = "cyqfjhcclkbxpbojgkar" # change this to any word
word, temp = "", s[0] # temp = s[0] for fence post problem
for i in range(1, len(s)): # starting from 1 not zero because we already add first char
x = temp[-1] # last word in var temp
y = s[i] # index in for-loop
if x <= y:
temp += s[i]
elif x > y:
if len(temp) > len(word): #storing longest substring so we can use temp for make another substring
word = temp
temp = s[i] #reseting var temp with last char in loop
if len(temp) > len(word):
word = temp
print("Longest substring in alphabetical order is:", word)
```
My code store longest substring at the moment in variable temp, then compare every string index in for-loop with last char in temp (temp[-1]) if index higher or same with (temp[-1]) then add that char from index in temp. If index lower than (temp[-1]) checking variable word and temp which one have longest substring, after that reset variable temp so we can make another substring until last char in strings.
s = 'cyqfjhcclkbxpbojgkar'
long_sub = '' #longest substring
temp = '' # temporarily hold current substr
if len(s) == 1: # if only one character
long_sub = s
else:
for i in range(len(s) - 1):
index = i
temp = s[index]
while index < len(s) - 1:
if s[index] <= s[index + 1]:
temp += s[index + 1]
else:
break
index += 1
if len(temp) > len(long_sub):
long_sub = temp
temp = ''
print(long_sub)
For comprehensibility, I also add this code snippet based on regular expressions. It's hard-coded and seems clunky. On the other hand, it seems to be the shortest and easiest answer to this problem. And it's also among the most efficient in terms of runtime complexity (see graph).
import re
def longest_substring(s):
substrings = re.findall('a*b*c*d*e*f*g*h*i*j*k*l*m*n*o*p*q*r*s*t*u*v*w*x*y*z*', s)
return max(substrings, key=len)
(Unfortunately, I'm not allowed to paste a graph here as a "newbie".)
Source + Explanation + Graph: https://blog.finxter.com/python-how-to-find-the-longest-substring-in-alphabetical-order/
Another way:
s = input("Please enter a sentence: ")
count = 0
maxcount = 0
result = 0
for char in range(len(s)-1):
if(s[char]<=s[char+1]):
count += 1
if(count > maxcount):
maxcount = count
result = char + 1
else:
count = 0
startposition = result - maxcount
print("Longest substring in alphabetical order is: ", s[startposition:result+1])

Python skipping my if statement

For some reason, this code doesn't work:
def pyglatin(word):
output = ""
wordlenedit = len(word)-1
wordlen = len(word)
fixer = 0
while fixer == 0:
for i in word:
if i == 'a' or i == 'e' or i == 'o' or i == 'i' or i == 'u':
fixer = 1
else:
wordlenedit -= 1
else:
output = word[wordlenedit:wordlen:1] + '-' + word[0:wordlenedit:1] + 'ay'
return output
To see the issues, click here. The problem appears to be that it's skipping the if statement that identifies vowels, but I'm not sure why. This results in some very odd outputs.
Your function does not work because you walk through the word, decrementing the splitting index for each consonant you encounter, starting at wordlenedit = len(word)-1.
At the end of your for loop, wordlenedit is equal to (length of the word) - 1 - (number of consonants). The function will only work if the first index of vowel in the word (starting at 0) is equal to the number of vowels - 1.
Also, the while loop is useless here, as you walk through the entire word in the for loop. It is even worse than that: the while loop will be an infinite loop if you have a word with no vowels (like "fly", as you don't check the "y")
This is a corrected version of your function, using the keyword break:
def pyglatin2(word):
output = ""
wordlenedit = 0
wordlen = len(word)
for l in word:
if l == 'a' or l == 'e' or l == 'o' or l == 'i' or l == 'u':
break
else:
wordlenedit += 1
output = word[wordlenedit:wordlen:1] + '-' + word[0:wordlenedit:1] + 'ay'
return output
However this function can be written in a much more concise/simple way, using Regular Expressions, like this:
import re
def pyglatin3(word):
# Get the first index of one of these: a, e, i, o, u
start = re.search("[aeiou]", word).start()
# Split the word
return word[start:] + "-" + word[0:start] + "ay"
If you want to do this without using regular expressions, the simplest way is to use enumerate:
def pyglatin(word):
for i, ch in enumerate(word):
if ch in 'aeiou':
return word[i:] + '-' + word[:i] + 'ay'

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