Python variable comment

[toaction]

In Python, variables do not possess their own comment syntax. The inspect.getdoc function actually returns the documentation of the associated data types.

# variable a
a = 10
print(inspect.getdoc(a))

int([x]) -> integer
int(x, base=10) -> integer

Convert a number or string to an integer, or return 0 if no arguments
are given.  If x is a number, return x.__int__().  For floating-point
numbers, this truncates towards zero.

If x is not a number or if base is given, then x must be a string,
bytes, or bytearray instance representing an integer literal in the
given base.  The literal can be preceded by '+' or '-' and be surrounded
by whitespace.  The base defaults to 10.  Valid bases are 0 and 2-36.
Base 0 means to interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4

[toaction]

Perhaps we can retrieve the comment information starting with # above variables by parsing the AST.

def get_variable_comment(source_code, variable_name):
    tree = ast.parse(source_code)
    for i, node in enumerate(ast.walk(tree)):
        if isinstance(node, ast.Assign):
            for target in node.targets:
                if isinstance(target, ast.Name) and target.id == variable_name:
                    lines = source_code.split('\n')
                    line_no = node.lineno - 1
                    comment_lines = []
                    for j in range(line_no - 1, -1, -1):
                        line = lines[j].strip()
                        if line.startswith('#'):
                            comment_lines.insert(0, line[1:].strip())
                        elif line == '':
                            continue
                        else:
                            break
                    return '\n'.join(comment_lines) if comment_lines else None
    return None

The prerequisite for this method is that we can obtain the source code where the variable is declared, and it only applies to variables defined in Python (not support for C variable).