N.2. Configuring the Colors
 The actual colors to be used are configured using the environment variable PG_COLORS (note plural). The value is a colon-separated list of key=value
The following keys are currently in use:
- error
- used to highlight the text “error” in error messages 
- warning
- used to highlight the text “warning” in warning messages 
- locus
- used to highlight location information (e.g., program name and file name) in messages 
 The default value is error=01;31:warning=01;35:locus=01 (01;31 = bold red, 01;35 = bold magenta, 01 = bold default color). 
Tip
This color specification format is also used by other software packages such as GCC, GNU coreutils, and GNU grep.

