Can't pass values to or from Python using JQuery

I am trying to pass values from a website to Python, and get a return passed back to be displayed. The input location is as follows:

<form>                                                                      <!-- create inputs -->
    <input type="text" id="WS" style="font-size:10pt; height:25px" required><br>    <!-- Wind speed input box -->
<br>
</form>

The user then clicks a button (in this case Lin):

<button id="Lin" style="height:30px; width:10%; background-color:#5188e0; border-color: black; color: white; font-weight: bold" title="Linear regression attempts to model the relationship between two variables by fitting a linear equation to observed data">Linear Regression</button>

This should pass the data to the following script:

$("#Lin").click(
    function(e) {
        $.get('/api/Lin/' + $('#WS').val(), function(data) {
            $('#Power_Est').val(data.value);
        });
    });

The output box is:

<form>
    <label>Estimated power output (KW/h):</label>                           <!-- Power label -->
    <input class="form-control" id="Power_Est" type="text" style="font-size:10pt; height:25px" placeholder="Power Estimate" readonly><br>   <!-- Power Estimate box -->
    <br>
</form>

The Python script I have is:

import flask as fl
import numpy as np
import joblib

app = fl.Flask(__name__)                                        # Create a new web app.

@app.route("/")                                                 # Add root route.
def home():                                                     # Home page
    return app.send_static_file("Front_Page.html")              # Return the index.html file

@app.route("/api/Lin/<float:speed>", methods = ["GET"])         # If the Linear Regression button is chosen
def Lin_Reg(speed):                                             # Call the linear regression function
    lin_model_load = joblib.load("Models/lin_reg.pkl")          # Reimport the linear regression model
    power_est = np.round(lin_model_load.predict(speed)[0], 3)   # Use the linear regression model to estimate the power for the user inputted speed
    return power_est                                            # Return the power estimate

Whenever I run the above, using flask, and http://127.0.0.1:5000/ I get the following error message:

127.0.0.1 - - [30/Dec/2020 21:07:19] "GET /api/Lin/20 HTTP/1.1" 404 -

Any suggestions on how to correct this?

Edit 1

Using the below:

def Lin_Reg(speed):                                             # Call the linear regression function
    print(speed)
    speed = speed.reshape(1, -1)
    lin_model_load = joblib.load("Models/lin_reg.pkl")          # Reimport the linear regression model
    power_est = lin_model_load.predict(speed) # Use the linear regression model to estimate the power for the user inputted speed
    return power_est                                            # Return the power estimate

print(Lin_Reg(20.0))

The error is:

--------------------------------------------------------------------------- AttributeError Traceback (most recent call last) in 6 return power_est # Return the power estimate 7 ----> 8 print(Lin_Reg(20.0))

in Lin_Reg(speed) 1 def Lin_Reg(speed): # Call the linear regression function 2 print(speed) ----> 3 speed = speed.reshape(1, -1) 4 lin_model_load = joblib.load("Models/lin_reg.pkl") # Reimport the linear regression model 5 power_est = lin_model_load.predict(speed) # Use the linear regression model to estimate the power for the user inputted speed

AttributeError: 'float' object has no attribute 'reshape'