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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 SplitEmailsAndAppendEmailDomain(self, address_list):
 """Splits a string of comma-separated emails, appending default domain."""

    result = []
    # Process email addresses, and build up a list.
    if isinstance(address_list, rdf_standard.DomainEmailAddress):
      address_list = [str(address_list)]
    elif isinstance(address_list, string_types):
      address_list = [address for address in address_list.split(",") if address]
    for address in address_list:
      result.append(self.AddEmailDomain(address))
    return result