查找一个公司的股票历史价格，并将其可视化。
company_name: str - 公司的名称。
To lookup a company's stock price history and visualize it: 

1. Find a financial data provider that offers this service such as Yahoo Finance, Google Finance, or Alpha Vantage.
2. Use the company_name variable to search for the stock symbol of the company.
3. Use the stock symbol to retrieve the historical stock prices.
4. Use a data visualization tool such as Matplotlib or Plotly to create a graph of the stock price history.

Here's an example code in Python using Yahoo Finance API:

```python
import yfinance as yf
import matplotlib.pyplot as plt

# Define company name and retrive the stock symbol
company_name = "Microsoft"
msft = yf.Ticker("MSFT")

# Get historical stock prices for the past 5 years
history = msft.history(period="5y")

# Visualize the stock price history in a line chart
history["Close"].plot(figsize=(10,5),title=f"{company_name} Stock Price History")
plt.xlabel("Date")
plt.ylabel("Closing Price ($)")
plt.show()
```