Hello @akharche! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file docs/demos/plotting.py:

Line 5:1: E122 continuation line missing indentation or outdented
Line 5:46: W291 trailing whitespace
Line 6:5: E128 continuation line under-indented for visual indent
Line 7:1: E122 continuation line missing indentation or outdented
Line 7:43: W291 trailing whitespace
Line 8:5: E128 continuation line under-indented for visual indent
Line 10:5: E128 continuation line under-indented for visual indent
Line 11:1: E122 continuation line missing indentation or outdented
Line 11:38: W291 trailing whitespace
Line 12:5: E128 continuation line under-indented for visual indent
Line 13:1: E122 continuation line missing indentation or outdented
Line 13:30: W291 trailing whitespace
Line 14:5: E128 continuation line under-indented for visual indent
Line 18:15: E231 missing whitespace after ':'
Line 19:15: E231 missing whitespace after ':'
Line 20:15: E231 missing whitespace after ':'
Line 21:17: E231 missing whitespace after ':'
Line 22:10: E231 missing whitespace after ':'
Line 36:17: E128 continuation line under-indented for visual indent
Line 37:31: E261 at least two spaces before inline comment
Line 43:27: E251 unexpected spaces around keyword / parameter equals
Line 43:29: E251 unexpected spaces around keyword / parameter equals
Line 52:1: W293 blank line contains whitespace
Line 58:13: E128 continuation line under-indented for visual indent
Line 59:13: E128 continuation line under-indented for visual indent
Line 67:9: E128 continuation line under-indented for visual indent
Line 68:9: E128 continuation line under-indented for visual indent