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How to avoid double backslashes in string literals being replaced with single backslash? [duplicate]

This question already has answers here:
How to write string literals in Python without having to escape them?
(6 answers)
Closed 7 months ago.
Python string replaces double backslash with a single backslash? How avoid replace? I need to keep \\n as it is.
Code:
if __name__ == "__main__":
str1 = '{"en":"M L\\n\\nL\\n\\nS","fr":""}'
print(str1)
print("{}".format(str1))
Output:
{"en":"M L\n\nL\n\nS","fr":""}
{"en":"M L\n\nL\n\nS","fr":""}
Expected output:
{"en":"M L\\n\\nL\\n\\nS","fr":""}

Use raw strings by inputting an r before the string:
r"M L\\n\\nL\\n\\nS"
This will ignore any and all escape characters.
Read more here: Raw Strings in Python

If you want to tell python to not convert \\ to \ you can specify your string as raw string. This will auto escape \ so they will be seen as they are. A raw string is a string that no characters can be escaped in it. You can do this by putting a r char before the string starts:
r"M L\\n\\nL\\n\\nS"
>>> "M L\\\\n\\\\nL\\\\n\\\\nS"
So you can see that python automatically escaped all the \ characters so when you use this string it will interpret as "M L\\n\\nL\\n\\nS".
If you have a multi line string you can do this the same way:
a = r"""abcdefg\n\t\a
dygkcy\d\wscd"""
note: There is no difference for ' and ".

how to replace '\' with '/' in python string [duplicate]

This question already has answers here:
python replace backslashes to slashes
(3 answers)
Closed 3 years ago.
I need to replace a python string that contains a number of '\':
String = 'A\BBC\CCB\:ABC'
goal = 'A/BBC/CCB/:ABC'
num = String.count('\')
String.replace('\','/')
But I keep getting error message:
SyntaxError: EOL while scanning string literal

The \ character in python has special uses. Eg. "\n" (newLine Character). In order to replace it in a string, you need to use one of the following:
String.replace('\\','/')
String.replace(r'\','/')
The "\" will look for the "\" character.
The r'\' will look for the raw interpretation of the string '\'

In your case you can do it like this:
string.replace('\\', '/', num)

Use '\', consider this situation:
print( "He said: \"Something about her.\"" );

How to use \ in a string in python [duplicate]

This question already has answers here:
How can I put an actual backslash in a string literal (not use it for an escape sequence)?
(4 answers)
Closed 4 years ago.
When I try to use
print variable + "\filename"
the slash isn't recognized as a string character,
however if I were to do
print variable + "\Filename"
capitalizing the first letter proceeding the slash... then the slash is recognized as a string character
The only thing I was able to find online is that in some cases a \ with a letter preceding it may be used to end a string of raw characters but I don't understand this.
So my question is why does this happen? And more importantly what is a way around this or a fix for this. Thank you.

You need to mark it as raw with the prefix r. Like this: print variable + r"\filename" Or alternatively you can escape it using a backslash print variable + "\\filename"

Replace \\ with \ in python [duplicate]

This question already has answers here:
python: replace a double \\ in a path with a single \
(3 answers)
Closed 8 years ago.
I Have a string having path of folder like below
>>> path
'\\\\sdgte\\ssdfdaa\\asfdsf'
I want to replace \\ with \ . I tried to replace but does not work as below
>>> path.replace('\\','\')
File "<input>", line 1
path.replace('\\','\')
^
SyntaxError: EOL while scanning string literal
Any Help will be highly appreciated.

There is no "\\" in the string. If you print it instead of looking at its representation you'll see the value that the string actually contains.
>>> print path
\\sdgte\ssdfdaa\asfdsf

You should use the escape charachter '\' to escape each \ in your string
path.replace('\\\\','\\')

you probably don't need to replace anything. \ is a special character in python that means "the next character, literally" in string literals. That is, if you want a string, containg a backslash, you'd probably type "\\":
>>> len('\\')
1
>>> print '\\'
\
>>> print '\\\\foo\\bar'
\\foo\bar
>>>

The reason you're getting that SyntaxError is the same reason you're seeing the doubled backslashes to begin with: backslash is the "escape" character, used to indicate the start of a special sequence, like "\n" for line feed, which would otherwise be difficult to represent in a string. The backslash character itself therefore has to be represented by a double backslash.
On the other hand, if you don't need to use any escape sequences within a string, you can preface the string with "r" instead of doubling the backslashes:
path.replace(r'\\', r'\')
path.replace(r'\\', '\\')
"r" indicates a "raw" string.

The problem you are running into, is that \ is an escape character. Instead of reading that as
replace '\\' with '\'
python is reading your argument as "replace the single backslash character with the single quotation mark character". The reason you are getting the error you are, is because python is ignoring your second single quotation mark because it thinks that is what you want it to do.
What you want is:
path.replace('\\\\', '\\')
you have to escape all backslashes because they are special.

Can '\' be in a Python string? [duplicate]

This question already has answers here:
How can I put an actual backslash in a string literal (not use it for an escape sequence)?
(4 answers)
Closed 8 years ago.
I program in Python in PyCharm and whenever I write '\' as a string it says that the following statements do nothing. For example:
Is there a way to fix this and make it work?
Thanks.

You need to double the backslash:
'/-\\'
as a single backslash has special meaning in a Python string as the start of an escape sequence. A double \\ results in the string containing a single backslash:
>>> print '/-\\'
/-\
If the backslash is not the last character in the string, you could use a r'' raw string as well:
>>> print r'\-/'
\-/

You need to scape them to be in the string, for example:
>>>s='\\'
>>>print s
\
You can also use the r (raw string) modifier in front of the string to include them easily but they can't end with an odd number of backslash. You can read more about string literals on the docs.