Parsing strings question 94

#1

I did not understand the whole code.

Please clarify.

#2 
def email_func(content):
    position = content.find('@')
    index = position
    if position!= -1:
        while index >=0 and content[index]!=' ':
            index-=1
        first_part = content[index+1:position]
        ending_position = content.find(' ',position)
        if ending_position == -1:
            second_part = content[position:]
        else:
            second_part = content[position:ending_position]
        return first_part + second_part
    else:
        return False