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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 is_name_owner( self, name, sender_script_pubkey ):
 """ Given the fully-qualified name and a sender's script pubkey, determine if the sender owns the name. The name must exist and not be revoked or expired at the current block. """

        if not self.is_name_registered( name ):
            # no one owns it 
            return False 

        owner = self.get_name_owner( name )
        if owner != sender_script_pubkey:
            return False 
        else:
            return True