def get_key_policy(KeyId=None, PolicyName=None):
    """
    Retrieves a policy attached to the specified key.
    See also: AWS API Documentation
    
    Examples
    The following example retrieves the key policy for the specified customer master key (CMK).
    Expected Output:
    
    :example: response = client.get_key_policy(
        KeyId='string',
        PolicyName='string'
    )
    
    
    :type KeyId: string
    :param KeyId: [REQUIRED]
            A unique identifier for the customer master key. This value can be a globally unique identifier or the fully specified ARN to a key.
            Key ARN Example - arn:aws:kms:us-east-1:123456789012:key/12345678-1234-1234-1234-123456789012
            Globally Unique Key ID Example - 12345678-1234-1234-1234-123456789012
            

    :type PolicyName: string
    :param PolicyName: [REQUIRED]
            String that contains the name of the policy. Currently, this must be 'default'. Policy names can be discovered by calling ListKeyPolicies .
            

    :rtype: dict
    :return: {
        'Policy': 'string'
    }
    
    
    """
    pass
