Consider the following syslog entry:

Jun $422$:$14$:$15$ server$1$ sshd$[9106]$ : Failed password for root from $10\mathrm{.}0\mathrm{.}2\mathrm{.}2$ port $22$ ssh$2$

Fill in the in this regex search, using only $\backslash$d and any modifiers necessary, what would you need to find any Process ID$,$ like the $9106$ in this entry? Note: assume that a Process ID must be at least one digit and can't be more than $5.$

Regex expression: $\backslash [()\backslash ]$