Could not find a version that satisfies the requirement tensorflow==1.4.1

[ASTRO063]

Could not find a version that satisfies the requirement tensorflow==1.4.1 (from -r requirements.txt (line 18)) (from versions: )
No matching distribution found for tensorflow==1.4.1 (from -r requirements.txt (line 18)). Help me with this.

[TooYang-moon]

Using python==3.6.x