content = content.replace("\\r\\n", "")

You need to double escape them.

You can also just use

text = '''
As she said these words her foot slipped, and in another moment, splash! she
was up to her chin in salt water. Her first idea was that she had somehow
fallen into the sea, “and in that case I can go back by railway,”
she said to herself.”'''

text = ' '.join(text.splitlines())

print(text)
# As she said these words her foot slipped, and in another moment, splash! she was up to her chin in salt water. Her first idea was that she had somehow fallen into the sea, “and in that case I can go back by railway,” she said to herself.”

If you are having issues with different forms of line break, try the str.splitlines() function and then re-join the result using the string you're after. Like this:

content = "".join(l for l in content.splitlines() if l)

Then, you just have to change the value within the quotes to what you need to join on. This will allow you to detect all of the line boundaries found here. Be aware though that str.splitlines() returns a list not an iterator. So, for large strings, this will blow out your memory usage. In those cases, you are better off using the file stream or io.StringIO and read line by line.

print(open('myfile.txt').read().replace('\n', ''))

When you write something like t.replace("\r\n", "") python will look for a carriage-return followed by a new-line.

Python will not replace carriage returns by themselves or replace new-line characters by themselves.

Consider the following:

t = "abc abracadabra abc"
t.replace("abc", "x")

• Will t.replace("abc", "x") replace every occurrence of the letter a with the letter x? No

• Will t.replace("abc", "x") replace every occurrence of the letter b with the letter x? No

• Will t.replace("abc", "x") replace every occurrence of the letter c with the letter x? No

What will t.replace("abc", "x") do?

t.replace("abc", "x") will replace the entire string "abc" with the letter "x"

Consider the following:

test_input = "\r\nAPPLE\rORANGE\nKIWI\n\rPOMEGRANATE\r\nCHERRY\r\nSTRAWBERRY"

t = test_input
for _ in range(0, 3):
    t = t.replace("\r\n", "")
    print(repr(t))

result2 = "".join(test_input.split("\r\n"))
print(repr(result2))

The output sent to the console is as follows:

'APPLE\rORANGE\nKIWI\n\rPOMEGRANATECHERRYSTRAWBERRY'
'APPLE\rORANGE\nKIWI\n\rPOMEGRANATECHERRYSTRAWBERRY'
'APPLE\rORANGE\nKIWI\n\rPOMEGRANATECHERRYSTRAWBERRY'
'APPLE\rORANGE\nKIWI\n\rPOMEGRANATECHERRYSTRAWBERRY'

Note that:

• str.replace() replaces every occurrence of the target string, not just the left-most occurrence.
• str.replace() replaces the target string, but not every character of the target string.

If you want to delete all new-line and carriage returns, something like the following will get the job done:

in_string = "\r\n-APPLE-\r-ORANGE-\n-KIWI-\n\r-POMEGRANATE-\r\n-CHERRY-\r\n-STRAWBERRY-"

out_string = "".join(filter(lambda ch: ch not in "\n\r", in_string))

print(repr(out_string))
# prints -APPLE--ORANGE--KIWI--POMEGRANATE--CHERRY--STRAWBERRY-

#write a file 
enter code here
write_File=open("sample.txt","w")
write_File.write("line1\nline2\nline3\nline4\nline5\nline6\n")
write_File.close()

#open a file without new line of the characters
open_file=open("sample.txt","r")
open_new_File=open_file.read()
replace_string=open_new_File.replace("\n",." ")
print(replace_string,end=" ")
open_file.close()

OUTPUT

line1 line2 line3 line4 line5 line6

regex will work in this case

r'(\r\n)+ pattern matches one or more occurrences of \r\n and then it replaced with single \r\n

import re

content = '\r\n\r\n\r\n\r\n\r\ntest'
content = re.sub(r'(\r\n)+', r'\r\n', content)  # '\r\ntest'