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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 assume_role(credentials, account, role):
 """Use FAWS provided credentials to assume defined role."""

    sts = boto3.client(
        'sts',
        aws_access_key_id=credentials['accessKeyId'],
        aws_secret_access_key=credentials['secretAccessKey'],
        aws_session_token=credentials['sessionToken'],
    )
    resp = sts.assume_role(
        RoleArn='arn:aws:sts::{}:role/{}'.format(account, role),
        RoleSessionName='fleece_assumed_role'
    )
    return {
        'accessKeyId': resp['Credentials']['AccessKeyId'],
        'secretAccessKey': resp['Credentials']['SecretAccessKey'],
        'sessionToken': resp['Credentials']['SessionToken'],
    }