<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _colourise(text: str, colour: str) -> str: """Colour text, if possible. Args: text: Text to colourise colour: Colour to display text in Returns: Colourised text, if possible """

    if COLOUR:
        text = style(text, fg=colour, bold=True)
    return text