def describe_policy(PolicyId=None):
    """
    Retrieves information about a policy.
    This operation can be called only from the organization's master account.
    See also: AWS API Documentation
    
    
    :example: response = client.describe_policy(
        PolicyId='string'
    )
    
    
    :type PolicyId: string
    :param PolicyId: [REQUIRED]
            The unique identifier (ID) of the policy that you want details about. You can get the ID from the ListPolicies or ListPoliciesForTarget operations.
            The regex pattern for a policy ID string requires 'p-' followed by from 8 to 128 lower-case letters or digits.
            

    :rtype: dict
    :return: {
        'Policy': {
            'PolicySummary': {
                'Id': 'string',
                'Arn': 'string',
                'Name': 'string',
                'Description': 'string',
                'Type': 'SERVICE_CONTROL_POLICY',
                'AwsManaged': True|False
            },
            'Content': 'string'
        }
    }
    
    
    """
    pass
