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Python Print Hex variable

I have hex variable that I want to print as hex
data = '\x99\x02'
print (data)
Result is: ™
I want to the python to print 0x9902
Thank you for your help

Please check this one.
data = r'\x99\x02'
a, b = [ x for x in data.split(r'\x') if x]
d = int(a+b, base=16)
print('%#x'%d)

You have to convert every char to its number - ord(char) - and convert every number to hex value - '{:02x}'.format() - and concatenate these values to string. And add string '0x'.
data = '\x99\x02'
print('0x' + ''.join('{:02x}'.format(ord(char)) for char in data))
EDIT: The same but first string is converted to bytes using encode('raw_unicode_escape')
data = '\x99\x02'
print('0x' + ''.join('{:02x}'.format(code) for code in data.encode('raw_unicode_escape')))
and if you have already bytes then you don't have to encode()
data = b'\x99\x02'
print('0x' + ''.join('{:02x}'.format(code) for code in data))
BTW: Similar way you can convert to binary using {:08b}
data = '\x99\x02'
print(''.join('{:08b}'.format(code) for code in data.encode('raw_unicode_escape')))

Convert String to hex and send via serial in Python

I want to convert the string 400AM49L01 to a hexadecimal form (and then into bytes) b'x\34\x30\x30\x41\x4d\x34\x39\x4c\x30', so I can write it with pySerial.
I already tried to convert the elements of a list, which contains the single hexadecimals like 0x31 (equals 4), into bytes, but this will result in b'400AM49L01'.
device = '400AM49L01'
device = device.encode()
device = bytes(device)
device = str(binascii.hexlify(device), 'ascii')
code = '0x'
text = []
count = 0
for i in device:
if count % 2 == 0 and count != 0:
text.append(code)
code = '0x'
count = 0
code += i
count += 1
text.append((code))
result = bytes([int(x, 0) for x in text])
Really looking forward for your help!

The following code will give the result you expecting.
my_str = '400AM49L01'
"".join(hex(ord(c)) for c in my_str).encode()
# Output
# '0x340x300x300x410x4d0x340x390x4c0x300x31'
What is it doing ?
In order to convert a string to hex, you need to convert each character to the integer value from the ascii table using ord().
Convert each int value to hex using the function hex().
Concatenate all hex value generated using join().
Encode the str to bytes using .encode().
Regards!

python Incorrect formatting Cyrillic

def inp(text):
tmp = str()
arr = ['.' for x in range(1, 40 - len(text))]
tmp += text + ''.join(arr)
print tmp
s=['tester', 'om', 'sup', 'jope']
sr=['тестер', 'ом', 'суп', 'жопа']
for i in s:
inp(i)
for i in sr:
inp(i)
Output:
tester.................................
om.....................................
sup....................................
jope...................................
тестер...........................
ом...................................
суп.................................
жопа...............................
Why is Python not properly handling Cyrillic? End of the line is not straight and scrappy. Using the formatting goes the same. How can this be corrected? thanks

Read this:
http://docs.python.org/2/howto/unicode.html
Basically, what you have in text parameter to inp function is a string. In Python 2.7, strings are bytes by default. Cyrilic characters are not mapped 1-1 to bytes when encoded in e.g. utf-8 encoding, but require more than one byte (usually 2 in utf-8), so when you do len(text) you don't get the number of characters, but number of bytes.
In order to get the number of characters, you need to know your encoding. Assuming it's utf-8, you can decode text to that encoding and it will print right:
#!/usr/bin/python
# coding=utf-8
def inp(text):
tmp = str()
utext = text.decode('utf-8')
l = len(utext)
arr = ['.' for x in range(1, 40 - l)]
tmp += text + ''.join(arr)
print tmp
s=['tester', 'om', 'sup', 'jope']
sr=['тестер', 'ом', 'суп', 'жопа']
for i in s:
inp(i)
for i in sr:
inp(i)
The important lines are these two:
utext = text.decode('utf-8')
l = len(utext)
where you first decode the text, which results in an unicode string. After that, you can use the built in len to get the length in characters, which is what you want.
Hope this helps.

Howto Remove Garbage Data from String

I'm in a situation where I have to use Python to read and write to an EEPROM on an embedded device. The first page (256 bytes) is used for non-volatile data storage. My problem is that the variables can vary in length, and I need to read a fixed amount.
For example, an string is stored at address 30 and can be anywhere from 6 to 10 bytes in length. I need to read the maximum possible length, because I don't know where it ends. What that does is it gives me excess garbage in the string.
data_str = ee_read(bytecount)
dbgmsg("Reading from EEPROM: addr = " + str(addr_low) + " value = " + str(data_str))
> Reading from EEPROM: addr = 30 value = h11c13����
I am fairly new to Python. Is there a way to automatically chop off that data in the string after it's been read in?

Do you mean something like:
>>> s = 'Reading from EEPROM: addr = 30 value = h11c13����'
>>> s
'Reading from EEPROM: addr = 30 value = h11c13\xef\xbf\xbd\xef\xbf\xbd\xef\xbf\xbd\xef\xbf\xbd'
>>> filter(lambda x: ord(x)<128,s)
'Reading from EEPROM: addr = 30 value = h11c13'
On python3, you'll need to to join the string:
''.join(filter(lambda x: ord(x)<128,s)
A version which works for python2 and python3 would be:
''.join(x for x in s if ord(x) < 128)
Finally, it is concieveable that the excess garbage could contain printing characters. In that case you might want to take only characters until you read a non-printing character, itertools.takewhile could be helpful...
import string #doesn't exist on python3.x, use the builtin `str` type instead.
from itertools import takewhile
printable = set(string.printable)
''.join(takewhile(lambda x: x in printable, s))

Python Convert Unicode-Hex utf-8 strings to Unicode strings

Have s = u'Gaga\xe2\x80\x99s' but need to convert to t = u'Gaga\u2019s'
How can this be best achieved?

s = u'Gaga\xe2\x80\x99s'
t = u'Gaga\u2019s'
x = s.encode('raw-unicode-escape').decode('utf-8')
assert x==t
print(x)
yields
Gaga’s

Where ever you decoded the original string, it was likely decoded with latin-1 or a close relative. Since latin-1 is the first 256 codepoints of Unicode, this works:
>>> s = u'Gaga\xe2\x80\x99s'
>>> s.encode('latin-1').decode('utf8')
u'Gaga\u2019s'

import codecs
s = u"Gaga\xe2\x80\x99s"
s_as_str = codecs.charmap_encode(s)[0]
t = unicode(s_as_str, "utf-8")
print t
prints
u'Gaga\u2019s'