AWS-CLI : to download IAM user with policy
You can use the below command to get all the policy attached to an iam user. (You must be having permissions to list-users and list-user-policies before using the below commands)

aws iam list-attached-user-policies --user-name username | jq -r '.AttachedPolicies[].PolicyArn' | awk -F'policy/' {'print $NF'}


(Make sure to replace username with some actual iam username in the above command)

If you want to get the list of all users and user-policies attached to those users, you can use the below one line command. The below command will get all the iam users and then will find the user-policies attached to that user and will put in a CSV file. The first column will contain username and second column will contain `policies separated by spaces. 

for u_name in $(aws iam list-users | jq -r '.Users[].UserName') ; do permissions="$(aws iam list-attached-user-policies --user-name ${u_name} | jq -r '.AttachedPolicies[].PolicyArn' | awk -F'policy/' {'print $NF'} | tr '\n' ' ')" ; echo "${u_name}, ${permissions}" &gt;&gt; iam_users.csv ; done