Write a program to compact spaces in a string i.e. Given a string you have to remove multiple occurrences of blank spaces by a single space and do that in a single pass of the arrays.

compact_spaces.py

def compact_spaces(a_string):
    space_check = []
    return_string = ''
    
    for char in a_string:
        if char == ' ' and char not in space_check:
            space_check.append(char)
            return_string += char
        elif char == ' ':
            continue
        elif char != ' ' and space_check != []:
            space_check.pop()
            return_string += char
        else:
            return_string += char
            
    return return_string

def compact_spaces_belmin(a_string):
    space_added = False
    return_string = ''
    
    for char in a_string:
        if char != ' ':
            return_string += char
            space_added = False
        elif not space_added:
            return_string += char
            space_added = True

    return return_string


print(compact_spaces('This is                        a         test'))
print(compact_spaces_belmin('This is                        a         test'))