masterUserPassword  
  The password associated with the admin user account for the cluster that is being created.
You can't use MasterUserPassword if ManageMasterPassword is true.
Constraints:
- Must be between 8 and 64 characters in length. 
- Must contain at least one uppercase letter. 
- Must contain at least one lowercase letter. 
- Must contain one number. 
- Can be any printable ASCII character (ASCII code 33-126) except - '(single quote),- "(double quote),- \,- /, or- @.