How does this programme works?Can you explain

Question

def convert_to_list(string):
list=[]
list[:0]=string
return(list)
#this function returns the character wise list of the string

Answer 1

list[:0]=string

That line is key.
That inserts each and every character from the string as a separate element in the list.

For example,
list = []
list[:0] = 'hello'
Now, list will be ['h', 'e', 'l', 'l', 'o'].
Assigning an iterable to a range in a list replaces the specified range with all iterable elements. That's just a feature of the Python programming language and the list data type.

If you want to see a little more discussion about assigning to these list ranges, check discussion at https://www.sololearn.com/Discuss/2744104/list-slice-problem-in-python

Note that your convert_to_list function is quite redundant. It is useful for educational purposes but any string can be converted to the same list by just wrapping your string in the list function like list('hello'). list('hello') is ['h', 'e', 'l', 'l', 'o'].