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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 bind(self):
 """Attempts to bind to the LDAP server using the credentials of the service account. :return: Bound LDAP connection object if successful or ``None`` if unsuccessful. """


        conn = self.initialize
        try:
            conn.simple_bind_s(
                current_app.config['LDAP_USERNAME'],
                current_app.config['LDAP_PASSWORD'])
            return conn
        except ldap.LDAPError as e:
            raise LDAPException(self.error(e.args))