email checker function | Python Fiddle

import re

def email_check(email):
    ''' This function check an email
    
    1. e-mail composed of a name and a domain part, these parts are separated by the symbol " @" ;
	2. the domain part is not shorter than 3 characters and no longer than 256, is a set of strings 
       of characters az 0 -9_ - and delimited ;
	3. in the domain of each such line between the points can not begin or end with a "-" ;
	4. name (up to @ ) does not exceed 128 characters , consists of characters a-z0-9"._- ;
	5. The name is not permitted two consecutive terms ;
	6. if the name is double quotation marks ", they must be paired ;
	7. in the name can meet the characters "!,:" but only in the double quotes .    
    
    '''
    email_temp = email.split("@")
    email_name = email_temp[0]
    email_domain = email_temp[1]
    if '..' in email_domain or '..' in email_name:
        raise ValueError('Error! You entered two periods in a row.')
    elif len(email_domain) < 3 or len(email_domain) > 256:
        raise ValueError('Error! Domain name must be from 3 to 255 characters.')
    elif len(email_name) > 128:
        raise ValueError('Error! The name of Email address must be less than 128 characters.')
    if '"' in email_name:
        if email_name.count('"')%2 != 0:
            raise ValueError('Error! Use double quotes.')
        else:
            email_name_parts = email_name.split('"')
            counter = 0
            parts_between_quotes = []
            parts_without_quotes = []
            while counter < len(email_name_parts):
                if counter%2 != 0:
                    parts_between_quotes.append(email_name_parts[counter])
                else:
                    parts_without_quotes.append(email_name_parts[counter])
                counter+=1
            for part in parts_between_quotes:
                chars = re.search('[a-zA-Z0-9!,:_-]+',part)
                if chars.group() != part:
                    raise ValueError('Error! Part of the Email name in quotes must consist of the characters a-zA-Z0-9!,:_-')
            for part in parts_without_quotes:
                chars = re.search('[a-zA-Z0-9_-]+',part)
                if chars.group() != part:
                    raise ValueError('Error! Part of the Email name without quotes must consist of the characters a-z0-9._-')
    else:
        chars = re.search('[a-zA-Z0-9"._-]+',email_name)
        if chars.group() != email_name:
            raise ValueError('Error! The name of Email address may consist of the characters a-z0-9"._-')
    domain_parts = email_domain.split(".")
    for part in domain_parts:
        if part.startswith('-') or part.endswith('-'):
            raise ValueError("Error! Domain name and domain area can not begin or end with '-'.")
        chars = re.search('[a-zA-Z0-9_-]+',part)
        if chars.group() != part:
            raise ValueError('Error! Domain name and domain zone must consist of the characters a-z0-9_-')    
    return "Email "+email+" is correct!"

print email_check('wlionheart@gmail.com')

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