> ## Documentation Index
> Fetch the complete documentation index at: https://prefect-bd373955-pytest-markdown.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Visualize flow structure
> Learn how to view the overall structure of your flow.
Get a quick view of the structure of your flow using the `.visualize()` method.
Calling this method attempts to produce a schematic diagram of your flow and tasks without
actually running your flow code.
Functions and code outside of flows or tasks will still be run when calling
`.visualize()`. This may have unintended consequences. Place your code into tasks to
avoid unintended
execution.
To use the `visualize()` method, you must havae Graphviz installed and on your PATH.
Please install Graphviz from [http://www.graphviz.org/download/](http://www.graphviz.org/download/).
Just installing the `graphviz` python package is not sufficient.
```python
from prefect import flow, task
@task(name="Print Hello")
def print_hello(name):
msg = f"Hello {name}!"
print(msg)
return msg
@task(name="Print Hello Again")
def print_hello_again(name):
msg = f"Hello {name}!"
print(msg)
return msg
@flow(name="Hello Flow")
def hello_world(name="world"):
message = print_hello(name)
message2 = print_hello_again(message)
if __name__ == "__main__":
hello_world.visualize()
```
Prefect cannot automatically produce a schematic for dynamic workflows, such as those with loops or
if/else control flow.
In this case, you can provide tasks with mock return values for use in the `visualize()` call.
```python
from prefect import flow, task
@task(viz_return_value=[4])
def get_list():
return [1, 2, 3]
@task
def append_one(n):
return n.append(6)
@flow
def viz_return_value_tracked():
l = get_list()
for num in range(3):
l.append(5)
append_one(l)
if __name__ == "__main__":
viz_return_value_tracked.visualize()
```
