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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def validate_social_account(account, url):
 """Verifies if a social account is valid. Examples: True 'http://twitter.com') False """


    request = urllib2.Request(urlparse.urljoin(url, account))
    request.get_method = lambda: 'HEAD'

    try:
        response = urllib2.urlopen(request)
    except urllib2.HTTPError:
        return False

    return response.code == 200