def list_signing_certificates(UserName=None, Marker=None, MaxItems=None):
    """
    Returns information about the signing certificates associated with the specified IAM user. If there are none, the action returns an empty list.
    Although each user is limited to a small number of signing certificates, you can still paginate the results using the MaxItems and Marker parameters.
    If the UserName field is not specified, the user name is determined implicitly based on the AWS access key ID used to sign the request for this API. Because this action works for access keys under the AWS account, you can use this action to manage root credentials even if the AWS account has no associated users.
    See also: AWS API Documentation
    
    Examples
    The following command lists the signing certificates for the IAM user named Bob.
    Expected Output:
    
    :example: response = client.list_signing_certificates(
        UserName='string',
        Marker='string',
        MaxItems=123
    )
    
    
    :type UserName: string
    :param UserName: The name of the IAM user whose signing certificates you want to examine.
            This parameter allows (per its regex pattern ) a string of characters consisting of upper and lowercase alphanumeric characters with no spaces. You can also include any of the following characters: =,.@-
            

    :type Marker: string
    :param Marker: Use this parameter only when paginating results and only after you receive a response indicating that the results are truncated. Set it to the value of the Marker element in the response that you received to indicate where the next call should start.

    :type MaxItems: integer
    :param MaxItems: (Optional) Use this only when paginating results to indicate the maximum number of items you want in the response. If additional items exist beyond the maximum you specify, the IsTruncated response element is true .
            If you do not include this parameter, it defaults to 100. Note that IAM might return fewer results, even when there are more results available. In that case, the IsTruncated response element returns true and Marker contains a value to include in the subsequent call that tells the service where to continue from.
            

    :rtype: dict
    :return: {
        'Certificates': [
            {
                'UserName': 'string',
                'CertificateId': 'string',
                'CertificateBody': 'string',
                'Status': 'Active'|'Inactive',
                'UploadDate': datetime(2015, 1, 1)
            },
        ],
        'IsTruncated': True|False,
        'Marker': 'string'
    }
    
    
    """
    pass
