How to split a string using an empty separator in Python

Strings are iterables and can be indexed, hence you don't really need to split it at all:

>>> for char in '11111':
...   print char
... 
1
1
1
1
1
>>> '11111'[4]
'1'

You can "split" it with a call to list, but it doesn't make much difference:

>>> for char in list('11111'):
...   print char
... 
1
1
1
1
1
>>> list('11111')[4]
'1'

So you only need to do this if your code explicitly expects a list. For example:

>>> list('11111').append('2')
>>> l = list('11111')
>>> l.append(2)
>>> l
['1', '1', '1', '1', '1', 2]

This doesn't work with a straight string:

>>> l.append('2')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'str' object has no attribute 'append'

In that case you would need:

>>> l += '2'
>>> l
'111112'

Method #1:

s="Amalraj"
l=[i for i in s]
print(l)

Output:

['A', 'm', 'a', 'l', 'r', 'a', 'j']

Method #2:

s="Amalraj"
l=list(s)
print(l)

Output:

['A', 'm', 'a', 'l', 'r', 'a', 'j']

Method #3:

import re; # importing regular expression module
s="Amalraj"
l=re.findall('.',s)
print(l)

Output:

['A', 'm', 'a', 'l', 'r', 'a', 'j']

Use list():

>>> list('1111')
['1', '1', '1', '1']

Alternatively, you can use map() (Python 2.7 only):

>>> map(None, '1111')
['1', '1', '1', '1']

Time differences:

$ python -m timeit "list('1111')"
1000000 loops, best of 3: 0.483 usec per loop
$ python -m timeit "map(None, '1111')"
1000000 loops, best of 3: 0.431 usec per loop

One can cast strings to list directly

>>> list('1111')
['1', '1', '1', '1']

or using list comprehensions

>>> [i for i in '1111']
['1', '1', '1', '1']

second way can be useful if one wants to split strings for substrings more than 1 symbol length

>>> some_string = '12345'
>>> [some_string[i:i+2] for i in range(0, len(some_string), 2)]
['12', '34', '5']