Any time you hear something referred to as a block or block of code it typically means the same thing. At least in programming.
There’s no better way to explain it than to show you visually! Don’t worry about understanding the code below, but understand that the chunks of code written at the same indentation level in Python make up a block of code. Notice the small gray arrow on line 4? That indicates a block of code belonging to whatever is on the line with the arrow - a function in this case.
A block of code is composed of several statements that are intended to execute when certain condition is met. In Python, a block of code is implemented using indentation.
An example,
if(true)
print "this is the first line of the block"
print "this is the second line of the block"
print "this is the third of the block"
else
print "this is the first line of another block"
print "this is the second line of another block"
print "this is the third of another block"